ForHosting KIT
Every API your product needs.
One key. One bill.
Hundreds of ready-made tasks — PDF, images, audio, OCR, text AI, scraping, data and more — behind a single REST API. Send a job, get a finished result by webhook. No servers, no per-model tokens, a price you can read.
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iOS & AndroidBuilding
WhatsAppComing
2015ready-made tools
6channels
1API & key
$0.002per call, from
The full catalog
Search or filter by category. Every capability is its own endpoint with a published price.
2015 tasks
📄 Documents & PDFAPI
Convert HTML to PDF
pixel-perfect
N
POST /pdf/from-html$0.040📄 Documents & PDFAPI
URL to PDF
save any web page as a PDF
N
POST /pdf/from-url$0.040📄 Documents & PDFAPI
Convert Markdown to PDF
styled output
N
POST /pdf/from-markdown$0.040📄 Documents & PDFAPI
Text to PDF
instant, in your browser or by API
N
POST /pdf/from-text$0.002📄 Documents & PDFAPI
JPG to PDF
combine images into one PDF
N
POST /pdf/from-images$0.002📄 Documents & PDFAPI
Merge PDF files
combine several into one
N
POST /pdf/merge$0.008📄 Documents & PDFAPI
Split a PDF
break it into separate files
N
POST /pdf/split$0.002📄 Documents & PDFAPI
Extract PDF pages
pull a page range
N
POST /pdf/extract-pages$0.002📄 Documents & PDFAPI
Delete pages from a PDF
remove any page
N
POST /pdf/remove-pages$0.002📄 Documents & PDFAPI
Reorder PDF pages
rearrange the order
N
POST /pdf/reorder-pages$0.002📄 Documents & PDFAPI
Rotate a PDF
turn pages 90, 180 or 270°
N
POST /pdf/rotate$0.002📄 Documents & PDFAPI
Watermark a PDF
stamp text on every page
N
POST /pdf/watermark-text$0.002📄 Documents & PDFAPI
Add a logo to a PDF
overlay on every page
N
POST /pdf/watermark-image$0.002📄 Documents & PDFAPI
Add page numbers to a PDF
auto-numbered
N
POST /pdf/page-numbers$0.002📄 Documents & PDFAPI
Add headers and footers to a PDF
N
POST /pdf/header-footer$0.002📄 Documents & PDFAPI
Bates numbering
stamp sequential legal IDs
N
POST /pdf/stamp$0.002📄 Documents & PDFAPI
Read PDF metadata
title, author and dates
N
POST /pdf/metadata-read$0.002📄 Documents & PDFAPI
Edit PDF metadata
set title, author, keywords
N
POST /pdf/metadata-write$0.002📄 Documents & PDFAPI
Remove PDF metadata
strip data before sharing
N
POST /pdf/metadata-clean$0.002📄 Documents & PDFAPI
Count PDF pages and words
quick stats
N
POST /pdf/stats$0.002📄 Documents & PDFTemporarily withdrawn
Convert PDF to JPG
one image per page
N
POST /pdf/to-images$0.040📄 Documents & PDFAPI
Make a PDF thumbnail
preview the first page
N
POST /pdf/thumbnail$0.040📄 Documents & PDFAPI
Extract text from a PDF
plain text out
N
POST /pdf/to-text$0.002📄 Documents & PDFAPI
Convert PDF to Markdown
clean output
N
POST /pdf/to-markdown$0.010📄 Documents & PDFSoon
Convert PDF to HTML
structured output
N
POST /pdf/to-html$0.052📄 Documents & PDFAPI
Fill a PDF form
populate fields from JSON
N
POST /pdf/fill-form$0.002📄 Documents & PDFAPI
Read PDF form fields
list fields and values
N
POST /pdf/form-read$0.002📄 Documents & PDFAPI
Flatten a PDF
lock forms and annotations
N
POST /pdf/flatten$0.002📄 Documents & PDFSoon
Compress a PDF
shrink size, keep quality
N
POST /pdf/compress$0.041📄 Documents & PDFSoon
Password-protect a PDF
encrypt with a key
N
POST /pdf/protect$0.042📄 Documents & PDFSoon
Remove a PDF password
decrypt your file
N
POST /pdf/unlock$0.042📄 Documents & PDFSoon
Convert PDF to PDF/A
ISO archival format
N
POST /pdf/to-pdfa$0.042📄 Documents & PDFSoon
Make a scan searchable
add an OCR layer
N
POST /pdf/ocr-layer$0.042📄 Documents & PDFSoon
Optimize a PDF for web
opens instantly
N
POST /pdf/linearize$0.042📄 Documents & PDFAPI
Compare two PDFs
see exactly what changed
N
POST /pdf/compare$0.002📄 Documents & PDFTemporarily withdrawn
Split a PDF by bookmarks
one file per chapter
N
POST /pdf/split-by-bookmark$0.002📄 Documents & PDFSoon
Convert Word to PDF
layout intact
N
POST /doc/word-to-pdf$0.051📄 Documents & PDFSoon
Convert PDF to Word
editable DOCX out
N
POST /doc/pdf-to-word$0.051📄 Documents & PDFSoon
Convert Excel to PDF
spreadsheets to PDF
N
POST /doc/excel-to-pdf$0.052📄 Documents & PDFAPI
Convert PDF to Excel
extract tables to XLSX
N
POST /doc/pdf-to-excel$0.010📄 Documents & PDFSoon
Convert PowerPoint to PDF
PPTX decks
N
POST /doc/ppt-to-pdf$0.052📄 Documents & PDFSoon
Get plain text from Word
strip a DOCX
N
POST /doc/docx-to-text$0.052📄 Documents & PDFSoon
Convert ODT to PDF
OpenDocument files
N
POST /doc/odt-to-pdf$0.052📄 Documents & PDFSoon
Convert EPUB to PDF
ebooks to print, coming soon
N
POST /doc/epub-to-pdf$0.052📄 Documents & PDFAPI
Generate a Word doc
build DOCX from data
N
POST /doc/generate-docx$0.002📄 Documents & PDFAPI
Create an invoice PDF
branded, from JSON
N
POST /pdf/invoice$0.040📄 Documents & PDFAPI
Create a receipt PDF
issue from JSON
N
POST /pdf/receipt$0.040📄 Documents & PDFAPI
Create certificates
diplomas at scale
N
POST /pdf/certificate$0.040📄 Documents & PDFAPI
Generate a contract PDF
template plus data
N
POST /pdf/contract$0.040📄 Documents & PDFAPI
Turn an HTML report into a PDF
paginated
N
POST /pdf/report$0.040📄 Documents & PDFAPI
Make shipping labels
print-ready barcodes
N
POST /pdf/label$0.002📄 Documents & PDFAPI
Create a quote PDF
branded estimates
N
POST /pdf/quote$0.040🔎 OCR & Data ExtractionAPI
Extract text from an image
OCR on web, API or Telegram
N
POST /ocr/image$0.010🔎 OCR & Data ExtractionAPI
Read a scanned PDF
get selectable text
N
POST /ocr/pdf$0.010🔎 OCR & Data ExtractionAPI
Turn handwriting into text
read handwritten notes
N
POST /ocr/handwriting$0.010🔎 OCR & Data ExtractionAPI
Extract tables to CSV
from images and PDFs
N
POST /ocr/table$0.010🔎 OCR & Data ExtractionAPI
Scan a receipt
photo to structured JSON
N
POST /ocr/receipt$0.010🔎 OCR & Data ExtractionAPI
Extract invoice data
line items, totals and tax to JSON
N
POST /ocr/invoice$0.009🔎 OCR & Data ExtractionAPI
Read a purchase order
into structured data
N
POST /ocr/purchase-order$0.010🔎 OCR & Data ExtractionAPI
Read a bank statement
extract every transaction to JSON
N
POST /ocr/bank-statement$0.010🔎 OCR & Data ExtractionAPI
Scan a business card
photo to a contact record
N
POST /ocr/business-card$0.010🔎 OCR & Data ExtractionAPI
Parse a CV
turn a resume into structured candidate data
N
POST /ocr/resume$0.003🔎 OCR & Data ExtractionAPI
Parse a job description
pull out requirements and skills
N
POST /ocr/job-post$0.003🔎 OCR & Data ExtractionAPI
Extract contract data
parties, dates, amounts and terms
N
POST /ocr/contract$0.003🔎 OCR & Data ExtractionAPI
Find clauses in a contract
isolate the terms that matter
N
POST /ocr/clause$0.003🔎 OCR & Data ExtractionAPI
Read a filled-in form
paper form to JSON
N
POST /ocr/form$0.010🔎 OCR & Data ExtractionAPI
Read an ID document
KYC data capture, with consent
N
POST /ocr/id-document$0.010🔎 OCR & Data ExtractionAPI
Read a passport's MRZ
parse the machine-readable zone
N
POST /ocr/mrz$0.010🔎 OCR & Data ExtractionAPI
Get the data behind a chart
recover the numbers
N
POST /ocr/chart$0.010🔎 OCR & Data ExtractionAPI
Screenshot to text
copyable text from any screenshot
N
POST /ocr/screenshot$0.010🔎 OCR & Data ExtractionAPI
Digitize a menu
photo to dishes and prices
N
POST /ocr/menu$0.010🔎 OCR & Data ExtractionAPI
Check if a document is signed
detect a signature
N
POST /ocr/signature-detect$0.010🔎 OCR & Data ExtractionAPI
Sort documents by type
classify what lands in your inbox
N
POST /ocr/document-classify$0.010🔎 OCR & Data ExtractionFree
Open an EML file
free in your browser: headers, body, files
N
POST /ocr/eml$0.002🔎 OCR & Data ExtractionAPI
Any document to JSON
extract against your own schema
N
POST /ocr/to-json$0.010🔎 OCR & Data ExtractionAPI
Key points of a document
the decisions, figures and risks
N
POST /ocr/key-points$0.003🔎 OCR & Data ExtractionAPI
Build a timeline from a document
get the chronology
N
POST /ocr/timeline$0.003🔎 OCR & Data ExtractionAPI
Pull citations from a paper
every reference, structured
N
POST /ocr/citation$0.003🔎 OCR & Data ExtractionAPI
Datasheet to attributes
pull structured product specs
N
POST /ocr/spec-sheet$0.003🔎 OCR & Data ExtractionFree
Find barcodes in a document
free in your browser
N
POST /ocr/barcode-doc$0.002🔎 OCR & Data ExtractionAPI
Detect a document's language
identify the language of a file
N
POST /ocr/language$0.003🔎 OCR & Data ExtractionAPI
Is this PDF scanned?
know if you need OCR before you pay
N
POST /ocr/scanned-or-native$0.002🖼️ ImagesSoon
Resize an image
online or by API
N
POST /image/resize$0.002🖼️ ImagesSoon
Bulk resize images
thousands at once
N
POST /image/resize-batch$0.002🖼️ ImagesSoon
Make responsive images
a full srcset in one go
N
POST /image/responsive-set$0.002🖼️ ImagesSoon
Crop an image
exact coordinates or aspect ratio, free
N
POST /image/crop$0.002🖼️ ImagesSoon
Smart crop
keeps the subject, not the centre
N
POST /image/smart-crop$0.002🖼️ ImagesSoon
Make thumbnails
square or rectangular, at scale
N
POST /image/thumbnail$0.002🖼️ ImagesSoon
Compress an image
smaller file, same quality
N
POST /image/compress$0.002🖼️ ImagesSoon
Convert to WebP
save 30% of the bytes
N
POST /image/to-webp$0.002🖼️ ImagesSoon
Convert to AVIF
the smallest modern format
N
POST /image/to-avif$0.002🖼️ ImagesSoon
Convert image format
JPG, PNG, GIF, BMP, TIFF, WebP
N
POST /image/convert$0.002🖼️ ImagesSoon
HEIC to JPG
make iPhone photos work everywhere
N
POST /image/heic-to-jpg$0.002🖼️ ImagesAPI
SVG to PNG
rasterize vectors at any resolution
N
POST /image/svg-to-png$0.040🖼️ ImagesSoon
Rotate an image
and auto-fix the orientation
N
POST /image/rotate$0.002🖼️ ImagesSoon
Flip an image
mirror it horizontally or vertically
N
POST /image/flip$0.002🖼️ ImagesSoon
Black-and-white an image
one-click grayscale
N
POST /image/grayscale$0.002🖼️ ImagesSoon
Apply a filter
sepia, blur, sharpen and more
N
POST /image/filter$0.002🖼️ ImagesSoon
Fix brightness & contrast
correct exposure in seconds
N
POST /image/brightness-contrast$0.002🖼️ ImagesSoon
Adjust saturation
dial colour intensity up or down
N
POST /image/saturation$0.002🖼️ ImagesSoon
Add a watermark
brand every image automatically
N
POST /image/watermark$0.002🖼️ ImagesSoon
Add text to an image
captions, prices and labels
N
POST /image/text-overlay$0.002🖼️ ImagesSoon
Blur part of an image
redact areas for privacy
N
POST /image/blur-region$0.002🖼️ ImagesSoon
Blur faces
anonymise people in photos automatically
N
POST /image/blur-faces$0.010🖼️ ImagesSoon
Blur license plates
redact plates before you publish
N
POST /image/blur-plates$0.010🖼️ ImagesFree
Read EXIF data
camera, date and GPS, free in browser
N
POST /image/exif-read$0.002🖼️ ImagesFree
Remove EXIF data
strip GPS before publishing, free
N
POST /image/exif-strip$0.002🖼️ ImagesFree
Extract a color palette
dominant colours, free in browser
N
POST /image/palette$0.002🖼️ ImagesFree
Find the dominant color
one swatch per image, free
N
POST /image/dominant-color$0.002🖼️ ImagesFree
Generate a BlurHash
loading placeholders, free in browser
N
POST /image/blurhash$0.002🖼️ ImagesFree
Perceptual hash
find duplicate images, free in browser
N
POST /image/phash$0.002🖼️ ImagesAPI
Compare two images
score how alike they are
N
POST /image/compare$0.002🖼️ ImagesSoon
Generate a favicon
every size and format from one image
N
POST /image/favicon$0.002🖼️ ImagesAPI
Open Graph images
dynamic social cards from a template
N
POST /image/og$0.040🖼️ ImagesSoon
Resize for social media
every platform size in one call
N
POST /image/social-variants$0.002🖼️ ImagesFree
Generate avatars
initials and geometric, free in browser
N
POST /image/avatar$0.002🖼️ ImagesSoon
Sprite sheets
pack images into one atlas
N
POST /image/sprite$0.002🖼️ ImagesFree
Validate an image
format, size and weight, free in browser
N
POST /image/validate$0.002🖼️ ImagesFree
Image to Base64
inline images as data URIs, free
N
POST /image/to-base64$0.002🖼️ ImagesAPI
Generate alt text
accessible, SEO-ready descriptions
N
POST /image/describe$0.010🖼️ ImagesAPI
Caption an image
describe what's in the picture
N
POST /image/caption$0.010🖼️ ImagesAPI
Auto-tag images
label a whole media library
N
POST /image/tag$0.010🖼️ ImagesAPI
Classify images
sort them into your own categories
N
POST /image/classify$0.010🖼️ ImagesAPI
Detect objects
find and locate with bounding boxes
N
POST /image/detect-objects$0.010🖼️ ImagesAPI
Detect NSFW content
moderate uploads before they go live
N
POST /image/moderate$0.010🖼️ ImagesAPI
Check image quality
reject blurry or dark uploads
N
POST /image/quality$0.010🖼️ ImagesAPI
Image to prompt
reverse-engineer a generation prompt
N
POST /image/prompt-from-image$0.010🖼️ ImagesAPI
Text to image
generate pictures from a prompt
N
POST /image/generate$0.002🖼️ ImagesAPI
Image variations
generate alternatives of a picture
N
POST /image/variations$0.002🖼️ ImagesAPI
Generate banners
ad and hero banners from a brief
N
POST /image/banner$0.002🖼️ ImagesAPI
Product mockups
place your product in a generated scene
N
POST /image/product-mockup$0.002🖼️ ImagesSoon
Remove the background
clean cutouts
N
POST /image/remove-background$0.061🖼️ ImagesSoon
Replace the background
any colour or scene, soon
N
POST /image/replace-background$0.062🖼️ ImagesTemporarily withdrawn
Upscale an image
2x and 4x, coming soon
N
POST /image/upscale$0.061🖼️ ImagesTemporarily withdrawn
Colorize photos
bring black-and-white to colour, soon
N
POST /image/colorize$0.062🖼️ ImagesSoon
Denoise an image
clean grain from low-light shots, soon
N
POST /image/denoise$0.062🖼️ ImagesSoon
Product packshots
pure-white product photos, soon
N
POST /image/packshot$0.062🖼️ ImagesSoon
Product shadow
add a natural drop shadow
N
POST /image/shadow$0.062🎧 Audio & VoiceAPI
Transcribe audio
90+ languages, published price
N
POST /audio/transcribe$0.004🎧 Audio & VoiceAPI
Transcript with timestamps
word-level timings
N
POST /audio/transcribe-timestamps$0.002🎧 Audio & VoiceAPI
Subtitles as .srt
ready-to-ship captions from any audio
N
POST /audio/subtitles-srt$0.002🎧 Audio & VoiceAPI
WebVTT captions
subtitles for HTML5 video
N
POST /audio/subtitles-vtt$0.002🎧 Audio & VoiceAPI
Identify speakers
who said what, and when
N
POST /audio/diarize$0.002🎧 Audio & VoiceAPI
Detect the spoken language
from any recording
N
POST /audio/detect-language$0.002🎧 Audio & VoiceAPI
Translate audio
hear one language, get another, published price
N
POST /audio/translate$0.004🎧 Audio & VoiceAPI
Summarize audio
an hour of talk, one page that matters
N
POST /audio/summarize$0.004🎧 Audio & VoiceAPI
Meeting minutes
decisions, owners and next steps, from audio
N
POST /audio/meeting-notes$0.004🎧 Audio & VoiceAPI
Action items
pull the to-dos out of any conversation
N
POST /audio/action-items$0.004🎧 Audio & VoiceAPI
Podcast chapters
timestamped chapters, generated for you
N
POST /audio/chapters$0.004🎧 Audio & VoiceAPI
Show notes
publish-ready notes from the episode audio
N
POST /audio/show-notes$0.004🎧 Audio & VoiceAPI
Keywords from audio
the topics inside any recording
N
POST /audio/keywords$0.004🎧 Audio & VoiceAPI
Audio to a blog post
turn a recording into an article
N
POST /audio/to-blog$0.004🎧 Audio & VoiceAPI
Moderate spoken audio
flag toxic or unsafe content
N
POST /audio/moderate$0.004🎧 Audio & VoiceAPI
Clean up a transcript
remove filler, fix punctuation
N
POST /audio/clean-transcript$0.003🎧 Audio & VoiceAPI
Search words in audio
find every mention, with timestamps
N
POST /audio/search$0.002🎧 Audio & VoiceAPI
Text to speech
natural voice audio from any text
N
POST /voice/tts$0.005🎧 Audio & VoiceAPI
SSML text to speech
control pauses, emphasis, pronunciation
N
POST /voice/tts-ssml$0.002🎧 Audio & VoiceAPI
Spanish text to speech
native Spanish voices from any text
N
POST /voice/tts-es$0.002🎧 Audio & VoiceSoon
Convert audio
MP3, WAV, OGG, M4A, FLAC
N
POST /audio/convert$0.077🎧 Audio & VoiceSoon
Trim audio
cut a clip out of a longer file
N
POST /audio/trim$0.077🎧 Audio & VoiceSoon
Normalize loudness
even volume across files
N
POST /audio/normalize$0.077🎧 Audio & VoiceSoon
Remove silence
strip dead air from a recording
N
POST /audio/remove-silence$0.077🎧 Audio & VoiceSoon
Reduce audio noise
clean up hiss and hum
N
POST /audio/denoise$0.077🎧 Audio & VoiceSoon
Merge audio
join several clips into one track
N
POST /audio/merge$0.077🎧 Audio & VoiceSoon
Split audio
cut a file into segments
N
POST /audio/split$0.077🎧 Audio & VoiceSoon
Audio metadata
read and write ID3 tags
N
POST /audio/metadata$0.077🎧 Audio & VoiceSoon
Waveform image
render a waveform or peaks JSON
N
POST /audio/waveform$0.077🎬 VideoSoon
Transcribe a video
every spoken word
N
POST /video/transcribe$0.079🎬 VideoSoon
Add subtitles to a video
auto-generated
N
POST /video/subtitles$0.079🎬 VideoSoon
Burn subtitles into a video
captions fixed onto the frames
N
POST /video/burn-subtitles$0.077🎬 VideoSoon
Get the audio from a video
pull out the sound track
N
POST /video/extract-audio$0.077🎬 VideoSoon
Convert a video
MP4, WebM, MOV, AVI, MKV
N
POST /video/convert$0.077🎬 VideoSoon
Compress a video
shrink the file for faster web delivery
N
POST /video/compress$0.077🎬 VideoSoon
Trim a video
cut a clip fast, without re-encoding
N
POST /video/trim$0.077🎬 VideoSoon
Grab a video thumbnail
a poster frame from any second
N
POST /video/thumbnail$0.077🎬 VideoSoon
Turn a video into a GIF
optimised animation
N
POST /video/gif$0.077🎬 VideoSoon
Resize a video
rescale to 1080p, 720p or any size
N
POST /video/resize$0.077🎬 VideoSoon
Add a watermark to a video
overlay your logo on the clip
N
POST /video/watermark$0.077🎬 VideoSoon
Extract frames from a video
export images at any interval
N
POST /video/frames$0.077🎬 VideoSoon
Read a video's metadata
duration, codecs, resolution, bitrate
N
POST /video/metadata$0.077🎬 VideoSoon
Make a video vertical
reframe 16:9 to 9:16 for Reels
N
POST /video/social-crop$0.077🎬 VideoSoon
Merge videos
join several clips into one file
N
POST /video/merge$0.077🎬 VideoSoon
Summarise a video
what it says, in one page
N
POST /video/summarize$0.084✍️ Text & AIAPI
Summarize a text
long in, the point out
N
POST /text/summarize$0.003✍️ Text & AIAPI
Summarize in bullet points
any text into key points
N
POST /text/summarize-bullets$0.003✍️ Text & AIAPI
Executive summary
decisions, figures and risks for leaders
N
POST /text/executive-summary$0.003✍️ Text & AIAPI
TL;DR
one sentence that earns the read
N
POST /text/tldr$0.003✍️ Text & AIAPI
Summarize a web page
give a link, get the summary
N
POST /text/summarize-url$0.046✍️ Text & AIAPI
Expand text
turn bullets into finished prose
N
POST /text/expand$0.003✍️ Text & AIAPI
Shorten text
cut the length, keep the meaning
N
POST /text/shorten$0.003✍️ Text & AIAPI
Rewrite text
say the same thing, differently
N
POST /text/rewrite$0.003✍️ Text & AIAPI
Paraphrase
reword text while keeping the meaning
N
POST /text/paraphrase$0.003✍️ Text & AIAPI
Simplify text
plain language, on demand
N
POST /text/simplify$0.003✍️ Text & AIAPI
Adjust reading level
rewrite for any CEFR level, A1 to C2
N
POST /text/reading-level$0.003✍️ Text & AIAPI
Change the tone
formal, casual, commercial, empathetic
N
POST /text/change-tone$0.003✍️ Text & AIAPI
Make text formal
turn casual writing into pro prose
N
POST /text/formalize$0.003✍️ Text & AIAPI
Make text sound human
soften stiff, robotic writing
N
POST /text/humanize$0.003✍️ Text & AIAPI
Check grammar
fix mistakes in 30+ languages
N
POST /text/grammar$0.003✍️ Text & AIAPI
Check spelling
catch typos in any language
N
POST /text/spellcheck$0.003✍️ Text & AIAPI
Fix punctuation
punctuate raw transcripts fast
N
POST /text/punctuation$0.003✍️ Text & AIAPI
Proofread
grammar, spelling, style and clarity in one pass
N
POST /text/proofread$0.003✍️ Text & AIFree
Readability score
Flesch, Gunning Fog, free in your browser
N
POST /text/readability$0.002✍️ Text & AIAPI
Detect language
identify the language of any text
N
POST /text/detect-language$0.003✍️ Text & AIAPI
Sentiment analysis
positive, negative, neutral, at scale
N
POST /text/sentiment$0.003✍️ Text & AIAPI
Detect emotion in text
joy, anger, sadness, fear
N
POST /text/emotion$0.003✍️ Text & AIAPI
Classify intent
understand what the user actually wants
N
POST /text/intent$0.003✍️ Text & AIAPI
Classify text
sort text into your own categories
N
POST /text/topic-classify$0.003✍️ Text & AIAPI
Moderate content
catch toxicity, hate and harassment
N
POST /text/moderate$0.003✍️ Text & AIAPI
Detect spam
filter junk from forms and comments
N
POST /text/spam$0.003✍️ Text & AIAPI
Find personal data
spot PII before it leaks
N
POST /text/detect-pii$0.003✍️ Text & AIAPI
Redact personal data
mask names, emails, cards, IDs
N
POST /text/redact-pii$0.003✍️ Text & AIAPI
Anonymize text
GDPR-safe, with the meaning intact
N
POST /text/anonymize$0.003✍️ Text & AIAPI
Extract entities
people, companies, places, dates
N
POST /text/extract-entities$0.003✍️ Text & AIAPI
Extract keywords
the terms that actually matter
N
POST /text/extract-keywords$0.003✍️ Text & AIAPI
Extract dates
normalised dates out of messy prose
N
POST /text/extract-dates$0.003✍️ Text & AIAPI
Extract amounts
currencies, totals and taxes
N
POST /text/extract-amounts$0.003✍️ Text & AIAPI
Extract questions
every question hiding in a document
N
POST /text/extract-questions$0.003✍️ Text & AIAPI
Extract claims
isolate the assertions in an argument
N
POST /text/extract-claims$0.003✍️ Text & AIAPI
Pull quotes
the lines worth putting in big type
N
POST /text/extract-quotes$0.003✍️ Text & AIAPI
Extract action items
turn notes into a task list
N
POST /text/extract-action-items$0.003✍️ Text & AIAPI
Text to JSON
loose text into your schema, validated
N
POST /text/to-json$0.003✍️ Text & AIAPI
Text to table
turn prose into a Markdown table
N
POST /text/to-table$0.003✍️ Text & AIAPI
Text to bullets
prose in, scannable list out
N
POST /text/to-bullets$0.003✍️ Text & AIAPI
Content outline
structure a piece before you write it
N
POST /text/outline$0.003✍️ Text & AIAPI
Compare two texts
explain what changed between versions
N
POST /text/compare$0.003✍️ Text & AIAPI
Text similarity
score how close two texts really are
N
POST /text/semantic-similarity$0.002✍️ Text & AIAPI
Generate an FAQ
built from your own content
N
POST /text/faq$0.003✍️ Text & AIAPI
Generate a quiz
questions and answers from any material
N
POST /text/quiz$0.003✍️ Text & AIAPI
Generate flashcards
spaced-repetition cards from a text
N
POST /text/flashcards$0.003✍️ Text & AIAPI
Ask your document
get the answer from your own files
N
POST /text/qa$0.003✍️ Text & AIAPI
Generate text
an LLM on a queue, at a price you can predict
N
POST /text/generate$0.003✍️ Text & AIAPI
Write a blog post
full draft from a title and a brief
N
POST /text/blog-post$0.003✍️ Text & AIAPI
Product descriptions
write a catalogue of 10,000 SKUs
N
POST /text/product-description$0.003✍️ Text & AIAPI
Ad copy
headlines that fit the character limit
N
POST /text/ad-copy$0.003✍️ Text & AIAPI
Landing page copy
hero, benefits, objections and CTA
N
POST /text/landing-copy$0.003✍️ Text & AIAPI
Write an email
from intent to a sendable draft
N
POST /text/email-compose$0.003✍️ Text & AIAPI
Subject lines
variants worth A/B testing
N
POST /text/email-subject$0.003✍️ Text & AIAPI
Reply to an email
draft an answer from the thread
N
POST /text/email-reply$0.003✍️ Text & AIAPI
Support replies
answers grounded in your help centre
N
POST /text/support-reply$0.003✍️ Text & AIAPI
Reply to reviews
answer each one without sounding robotic
N
POST /text/review-reply$0.003✍️ Text & AIAPI
Social posts
one idea, every platform's format
N
POST /text/social-post$0.003✍️ Text & AIAPI
Social thread
turn an article into a thread that holds up
N
POST /text/social-thread$0.003✍️ Text & AIAPI
Generate hashtags
relevant tags, not just popular ones
N
POST /text/hashtags$0.003✍️ Text & AIAPI
Write headlines
titles that earn the click honestly
N
POST /text/headline$0.003✍️ Text & AIAPI
A/B copy variants
generate options, you pick the winner
N
POST /text/ab-variants$0.003✍️ Text & AIAPI
Name ideas
brand and product names on demand
N
POST /text/name-ideas$0.003✍️ Text & AIAPI
Slogans
taglines that stick, in batches
N
POST /text/slogan$0.003✍️ Text & AIAPI
Write a bio
profile-ready, in the right length
N
POST /text/bio$0.003✍️ Text & AIAPI
Cover letter
tailored to the job in minutes
N
POST /text/cover-letter$0.003✍️ Text & AIAPI
Interview questions
for any role, ready to ask
N
POST /text/interview-questions$0.003✍️ Text & AIAPI
Video script
for YouTube, TikTok or a demo
N
POST /text/script$0.003✍️ Text & AIAPI
Newsletter
a full issue from your notes
N
POST /text/newsletter$0.003✍️ Text & AIAPI
Changelog
turn commits into release notes
N
POST /text/changelog$0.003✍️ Text & AIAPI
Content ideas
a batch of angles to write about
N
POST /text/content-ideas$0.003✍️ Text & AIAPI
Score leads
rank prospects by how likely they buy
N
POST /text/lead-score$0.003✍️ Text & AIAPI
Route tickets
send each one to the right team
N
POST /text/ticket-route$0.003✍️ Text & AIAPI
Summarize reviews
what customers say, in one read
N
POST /text/review-summary$0.003✍️ Text & AIAPI
Analyze feedback
themes and sentiment from open text
N
POST /text/feedback-analyze$0.003✍️ Text & AIAPI
Categorize expenses
sort transactions automatically
N
POST /text/expense-categorize$0.003✍️ Text & AIAPI
Categorize products
sort a catalogue into taxonomy
N
POST /text/product-categorize$0.003✍️ Text & AIAPI
Product attributes
pull specs out of descriptions
N
POST /text/product-attributes$0.003✍️ Text & AIAPI
Normalize product data
clean, consistent catalogues
N
POST /text/product-normalize$0.003✍️ Text & AIAPI
Analyze logs
find the errors that matter in the noise
N
POST /text/log-analyze$0.003✍️ Text & AIFree
Word counter
words, characters, sentences, free in your browser
A
POST /text/word-count$0.002✍️ Text & AIFree
Number to words
spell amounts in English and Spanish
P
POST /text/number-to-words$0.002✍️ Text & AIFree
Case converter
camel snake title free in browser
A
POST /text/case-convert$0.002✍️ Text & AIFree
NATO phonetic alphabet
encode and decode free in your browser
P
POST /text/nato-phonetic$0.002✍️ Text & AIFree
Caesar cipher & ROT13
encode and decode free in your browser
P
POST /text/caesar-cipher$0.002✍️ Text & AIFree
Extract emails from text
free in your browser
P
POST /text/extract-emails$0.002🌐 TranslationAPI
Translate text
100+ languages in your browser, or by API
N
POST /translate/text$0.003🌐 TranslationAPI
Translate an HTML page
keep every tag intact
N
POST /translate/html$0.003🌐 TranslationAPI
Translate a JSON locale file
keys intact
N
POST /translate/json$0.003🌐 TranslationAPI
Translate a CSV
pick the columns, keep the rest
N
POST /translate/csv$0.003🌐 TranslationAPI
Translate Markdown
docs translated, syntax unbroken
N
POST /translate/markdown$0.003🌐 TranslationAPI
Translate subtitles
.srt and .vtt, timings preserved
N
POST /translate/srt$0.003🌐 TranslationAPI
Translate a PDF
get a translated PDF back
N
POST /translate/pdf$0.011🌐 TranslationAPI
Translate a Word document
formatting intact, soon
N
POST /translate/docx$0.057🌐 TranslationAPI
Translate with a glossary
your terms, every time
N
POST /translate/glossary$0.003🌐 TranslationAPI
Translate formal or informal
choose tú vs usted
N
POST /translate/formality$0.003🌐 TranslationAPI
Translate keeping the tone
marketing copy that lands
N
POST /translate/tone-preserve$0.003🌐 TranslationAPI
Translate for SEO
hit the keyword people search
N
POST /translate/seo$0.003🌐 TranslationAPI
Translate a product catalog
10,000 items in one job
N
POST /translate/catalog$0.003🌐 TranslationAPI
Translate an email
reply support in their language
N
POST /translate/email$0.003🌐 TranslationAPI
Translate code comments
never touch the code
N
POST /translate/code-comments$0.003🌐 TranslationAPI
Transliterate
Cyrillic, Greek, Arabic, CJK to Latin
N
POST /translate/transliterate$0.003🌐 TranslationAPI
Explain slang
decode idioms, don't translate literally
N
POST /translate/slang$0.003🌐 TranslationAPI
Adapt regional variants
es-ES, es-MX or neutral Spanish
N
POST /translate/regional$0.003🌐 TranslationAPI
Back-translate to check
translate it back to verify
N
POST /translate/back$0.003🌐 TranslationFree
Format numbers & currency
free in your browser, any locale
N
POST /locale/format-number$0.002🌐 TranslationFree
Localize dates
free in your browser, any locale's format
N
POST /locale/format-date$0.002🌐 TranslationFree
Localize units
metric or imperial, free in your browser
N
POST /locale/units$0.002🌐 TranslationAPI
Translate text in a photo
read it and translate it
N
POST /translate/ocr$0.011🌐 TranslationFree
Sort a list alphabetically
accents and numbers handled
G
POST /locale/sort$0.002🕸️ Web Scraping & MonitoringAPI
Screenshot a website
published price
N
POST /web/screenshot$0.040🕸️ Web Scraping & MonitoringAPI
Full-page screenshot
the whole scroll
N
POST /web/screenshot-full$0.040🕸️ Web Scraping & MonitoringAPI
Mobile screenshot
render as iPhone, Android or tablet
N
POST /web/screenshot-device$0.040🕸️ Web Scraping & MonitoringAPI
Screenshot one element
capture just a CSS selector
N
POST /web/screenshot-element$0.040🕸️ Web Scraping & MonitoringAPI
Scheduled screenshots
daily or weekly, delivered to you
N
POST /web/screenshot-scheduled$0.040🕸️ Web Scraping & MonitoringAPI
Render a JavaScript page
get the DOM after JS runs
N
POST /web/render$0.040🕸️ Web Scraping & MonitoringAPI
Web page to Markdown
clean text, ready for an LLM
N
POST /web/to-markdown$0.040🕸️ Web Scraping & MonitoringAPI
Web page to text
strip a page to readable prose
N
POST /web/to-text$0.040🕸️ Web Scraping & MonitoringAPI
Extract an article
reader mode
N
POST /web/article$0.040🕸️ Web Scraping & MonitoringAPI
Scrape a website
point at CSS selectors, get JSON
N
POST /web/scrape-selector$0.040🕸️ Web Scraping & MonitoringAPI
Scrape with AI
describe what you want in plain words
N
POST /web/scrape-ai$0.046🕸️ Web Scraping & MonitoringAPI
Scrape to a schema
give a JSON Schema, get valid data
N
POST /web/scrape-schema$0.046🕸️ Web Scraping & MonitoringAPI
Crawl a website
walk every page, respecting robots.txt
N
POST /web/crawl$0.040🕸️ Web Scraping & MonitoringAPI
Extract links
every link on a page, internal and external
N
POST /web/links$0.002🕸️ Web Scraping & MonitoringAPI
Extract images
list every image with its alt text
N
POST /web/images$0.002🕸️ Web Scraping & MonitoringAPI
Web table to CSV
scrape tables into a spreadsheet
N
POST /web/tables$0.040🕸️ Web Scraping & MonitoringAPI
Audit contact details
check the info on your own pages
N
POST /web/contacts$0.002🕸️ Web Scraping & MonitoringAPI
Link preview
title, description and image for any URL
N
POST /web/link-preview$0.002🕸️ Web Scraping & MonitoringFree
Read meta tags
free in your browser: meta, OG, Twitter
N
POST /web/metadata$0.002🕸️ Web Scraping & MonitoringFree
Extract JSON-LD
free in your browser, pull Schema.org data
N
POST /web/schema$0.002🕸️ Web Scraping & MonitoringFree
RSS to JSON
free in your browser, parse RSS and Atom
N
POST /web/rss-to-json$0.002🕸️ Web Scraping & MonitoringAPI
Find the RSS feed
for a site that hides it away
N
POST /web/rss-discover$0.002🕸️ Web Scraping & MonitoringAPI
Create an RSS feed
for a site that doesn't have one
N
POST /web/make-rss$0.040🕸️ Web Scraping & MonitoringAPI
Extract product data
name, price, stock and images
N
POST /web/product-extract$0.046🕸️ Web Scraping & MonitoringAPI
Extract a price
read the current price off any page
N
POST /web/price-extract$0.046🕸️ Web Scraping & MonitoringAPI
Check if it's in stock
right now, from the product page
N
POST /web/stock-extract$0.046🕸️ Web Scraping & MonitoringAPI
Extract reviews
pull ratings and opinions into JSON
N
POST /web/reviews-extract$0.046🕸️ Web Scraping & MonitoringAPI
Extract a job posting
structure a vacancy from its page
N
POST /web/job-extract$0.046🕸️ Web Scraping & MonitoringAPI
Monitor a page for changes
get a webhook when it changes
N
POST /web/monitor-changes$0.002🕸️ Web Scraping & MonitoringAPI
Monitor visual changes
spot when a page *looks* different
N
POST /web/monitor-visual$0.040🕸️ Web Scraping & MonitoringAPI
Track a price
watch competitors on a schedule
N
POST /web/monitor-price$0.040🕸️ Web Scraping & MonitoringAPI
Back-in-stock alerts
know the moment it returns
N
POST /web/monitor-stock$0.040🕸️ Web Scraping & MonitoringAPI
Monitor a keyword
watch a word appear or vanish
N
POST /web/monitor-keyword$0.002🕸️ Web Scraping & MonitoringAPI
Monitor uptime
status and latency, on your schedule
N
POST /web/uptime$0.002🕸️ Web Scraping & MonitoringAPI
Multi-region uptime
check from the edge, worldwide
N
POST /web/uptime-multi$0.002🕸️ Web Scraping & MonitoringAPI
Check an SSL certificate
issuer, chain and days left
N
POST /web/ssl-check$0.002🕸️ Web Scraping & MonitoringAPI
Check domain expiry
never lose one to a missed renewal
N
POST /web/domain-expiry$0.002🕸️ Web Scraping & MonitoringAPI
WHOIS lookup
registrar, dates and nameservers via RDAP
N
POST /web/whois$0.002🕸️ Web Scraping & MonitoringAPI
DNS lookup
A, AAAA, MX, TXT, NS, CNAME and SOA records
N
POST /web/dns$0.002🕸️ Web Scraping & MonitoringAPI
Check DNS propagation
query resolvers worldwide at once
N
POST /web/dns-propagation$0.002🕸️ Web Scraping & MonitoringAPI
Inspect HTTP headers
see every response header
N
POST /web/headers$0.002🕸️ Web Scraping & MonitoringAPI
Check security headers
grade CSP, HSTS, X-Frame-Options
N
POST /web/security-headers$0.002🕸️ Web Scraping & MonitoringAPI
Check redirects
follow the whole chain, hop by hop
N
POST /web/redirect-chain$0.002🕸️ Web Scraping & MonitoringAPI
Check HTTP status
code and latency for a list of URLs
N
POST /web/status$0.002🕸️ Web Scraping & MonitoringAPI
Find broken links
catch the 404s before your users do
N
POST /web/broken-links$0.002🕸️ Web Scraping & MonitoringAPI
Detect a site's technology
what it's really built with
N
POST /web/tech-detect$0.040🕸️ Web Scraping & MonitoringAPI
Audit cookies
inventory trackers for GDPR compliance
N
POST /web/cookie-audit$0.040🕸️ Web Scraping & MonitoringAPI
Accessibility audit
WCAG issues and the offending element
N
POST /web/accessibility$0.040🕸️ Web Scraping & MonitoringAPI
Measure Core Web Vitals
LCP, CLS and INP in a lab run
N
POST /web/vitals$0.040🕸️ Web Scraping & MonitoringAPI
Prerender for bots
serve rendered HTML to crawlers
N
POST /web/prerender$0.040📈 SEOAPI
Generate meta tags
fit the pixel limit
N
POST /seo/meta-generate$0.003📈 SEOAPI
Audit a page for SEO
issues ranked by lost traffic
N
POST /seo/audit$0.040📈 SEOFree
Check heading structure
free in your browser, H1 to H6
N
POST /seo/headings$0.002📈 SEOFree
Keyword density
what a page is about, free in your browser
N
POST /seo/keyword-density$0.002📈 SEOAPI
Audit internal links
find orphan pages and link sinks
N
POST /seo/internal-links$0.002📈 SEOFree
Check the canonical tag
free in-browser, catch bad ones
N
POST /seo/canonical-check$0.002📈 SEOFree
Validate hreflang
free in your browser, check return links
N
POST /seo/hreflang-check$0.002📈 SEOAPI
Analyze robots.txt
know exactly what you're blocking
N
POST /seo/robots-analyze$0.002📈 SEOFree
Validate a sitemap
broken URLs and bad lastmod, in-browser
N
POST /seo/sitemap-validate$0.002📈 SEOFree
Sitemap to JSON
flatten an index into a URL list, free
N
POST /seo/sitemap-to-json$0.002📈 SEOAPI
Generate a sitemap
crawl a site, emit a valid sitemap.xml
N
POST /seo/sitemap-generate$0.002📈 SEOAPI
Generate JSON-LD
valid structured data for any page type
N
POST /seo/schema-generate$0.003📈 SEOFree
Validate Open Graph
see the card before you post it, free
N
POST /seo/og-validate$0.002📈 SEOAPI
Audit alt text
find what's missing and write the fix
N
POST /seo/alt-text-audit$0.066📈 SEOAPI
SEO content brief
the outline a page needs to rank
N
POST /seo/content-outline$0.003📈 SEOAPI
Write click-worthy titles
variants that earn the click
N
POST /seo/title-variants$0.003📈 SEOFree
SEO readability score
how easy a page is to read, free
N
POST /seo/readability$0.002📈 SEOAPI
Cluster keywords by intent
group thousands at once
N
POST /seo/keyword-cluster$0.002📈 SEOAPI
YouTube description
title, tags and chapters, done for you
N
POST /seo/youtube-meta$0.003📈 SEOSoon
Optimize images for SEO
right format, size and filename
N
POST /seo/image-optimize$0.002📈 SEOFree
Validate a redirect map
find loops and chains before launch
G
POST /seo/redirect-map-validate$0.002🗂️ Data & FilesFree
CSV to JSON
free in your browser, or by API
N
POST /data/csv-to-json$0.002🗂️ Data & FilesFree
JSON to CSV
flatten to a spreadsheet, free online
N
POST /data/json-to-csv$0.002🗂️ Data & FilesAPI
Excel to JSON
read XLSX sheets, published price
N
POST /data/xlsx-to-json$0.002🗂️ Data & FilesAPI
JSON to Excel
a formatted XLSX from your data
N
POST /data/json-to-xlsx$0.002🗂️ Data & FilesFree
XML to JSON
attributes kept, free in your browser
N
POST /data/xml-to-json$0.002🗂️ Data & FilesFree
JSON to XML
free in your browser, or by API
N
POST /data/json-to-xml$0.002🗂️ Data & FilesFree
YAML to JSON
convert either way, free online
N
POST /data/yaml-json$0.002🗂️ Data & FilesFree
Validate JSON Schema
the exact error path, free
N
POST /data/json-validate$0.002🗂️ Data & FilesAPI
Repair broken JSON
commas, quotes, cut LLM output
N
POST /data/json-repair$0.003🗂️ Data & FilesFree
Format JSON
pretty-print online, free in your browser
N
POST /data/json-format$0.002🗂️ Data & FilesFree
Minify JSON
strip whitespace, free in your browser
N
POST /data/json-minify$0.002🗂️ Data & FilesFree
JSON to HTML table
a styled table, free online
N
POST /data/json-to-html$0.002🗂️ Data & FilesFree
Clean a CSV
trim, fix encoding, drop empties, free
N
POST /data/clean-csv$0.002🗂️ Data & FilesFree
Remove duplicate rows
dedupe a CSV, free online
N
POST /data/dedupe-csv$0.002🗂️ Data & FilesAPI
Fuzzy dedupe
catch duplicates not spelled the same
N
POST /data/dedupe-semantic$0.002🗂️ Data & FilesFree
Merge & join CSV files
inner, left and outer joins
N
POST /data/merge-csv$0.002🗂️ Data & FilesFree
Transform a CSV
rename, compute and reshape columns
N
POST /data/transform-csv$0.002🗂️ Data & FilesFree
Filter CSV rows
keep only what matches, free online
N
POST /data/filter-csv$0.002🗂️ Data & FilesFree
CSV statistics
profile nulls, ranges, distributions
N
POST /data/csv-stats$0.002🗂️ Data & FilesAPI
Normalize names & addresses
one clean record from ten
N
POST /data/normalize-names$0.003🗂️ Data & FilesFree
Normalize dates
any format in, ISO-8601 out, free
N
POST /data/normalize-dates$0.002🗂️ Data & FilesFree
Convert to UTF-8
detect encoding, fix mojibake, free
N
POST /data/to-utf8$0.002🗂️ Data & FilesFree
Compare text
line, word and character diff, free
N
POST /data/diff$0.002🗂️ Data & FilesFree
Create a ZIP from text entries
free in your browser
N
POST /data/zip$0.002🗂️ Data & FilesFree
Unzip a file
list and extract archives, free online
N
POST /data/unzip$0.002🗂️ Data & FilesFree
Gzip
compress and decompress: gzip, deflate, brotli
N
POST /data/gzip$0.002🗂️ Data & FilesFree
Mock data generator
realistic test fixtures, free
N
POST /data/fake$0.002🗂️ Data & FilesFree
Markdown to HTML
CommonMark and GFM, free online
N
POST /data/markdown-to-html$0.002🗂️ Data & FilesFree
HTML to Markdown
clean Markdown from messy HTML
N
POST /data/html-to-markdown$0.002🗂️ Data & FilesFree
HTML to text
strip tags, keep it readable, free
N
POST /data/html-to-text$0.002🗂️ Data & FilesFree
Sanitize HTML
strip XSS from user HTML, free online
N
POST /data/html-sanitize$0.002🗂️ Data & FilesFree
Minify HTML
shrink markup without breaking it, free
N
POST /data/html-minify$0.002🗂️ Data & FilesFree
Minify CSS
shrink stylesheets, free in your browser
N
POST /data/css-minify$0.002🗂️ Data & FilesFree
Minify JavaScript
no build step, free in your browser
N
POST /data/js-minify$0.002🗂️ Data & FilesFree
Convert units
length, weight, volume, temperature, free
N
POST /data/convert-units$0.002🗂️ Data & FilesFree
Convert colors
HEX, RGB, HSL, LAB and CMYK, free
N
POST /data/color-convert$0.002✅ ValidationFree
Check an email address
free in your browser, RFC-correct
N
POST /verify/email-syntax$0.002✅ ValidationAPI
Verify an email exists
syntax, domain and MX
N
POST /verify/email-mx$0.002✅ ValidationAPI
Spot throwaway emails
block temporary signups
N
POST /verify/email-disposable$0.002✅ ValidationFree
Find role emails
spot info@, admin@, free in your browser
N
POST /verify/email-role$0.002✅ ValidationFree
Fix email typos
catch gmial.com free in your browser
N
POST /verify/email-typo$0.002✅ ValidationAPI
Clean your email list
verify your own subscribers
N
POST /verify/email-batch$0.002✅ ValidationFree
Validate a phone number
normalise to E.164 in your browser
N
POST /verify/phone$0.002✅ ValidationAPI
Look up a phone carrier
country, carrier and line type
N
POST /verify/phone-carrier$0.002✅ ValidationFree
Validate an IBAN
checksum and country format, in-browser
N
POST /verify/iban$0.002✅ ValidationFree
Check a SWIFT/BIC code
format check, free in your browser
N
POST /verify/swift$0.002✅ ValidationAPI
Check an EU VAT number
verified against VIES
N
POST /verify/vat$0.002✅ ValidationFree
Check a tax ID format
40+ countries, free in your browser
N
POST /verify/tax-id$0.002✅ ValidationFree
Validate a card number
Luhn check, nothing ever stored
N
POST /verify/card-luhn$0.002✅ ValidationFree
Detect a card brand
Visa, Mastercard, Amex in-browser
N
POST /verify/card-type$0.002✅ ValidationAPI
Locate an IP address
country, city and ASN
N
POST /verify/ip-geo$0.002✅ ValidationAPI
Detect VPN and proxy
flag datacenter and Tor
N
POST /verify/ip-vpn$0.002✅ ValidationAPI
Score bot traffic
how likely a request is automated
N
POST /verify/bot-score$0.002✅ ValidationFree
Validate a URL
parse and normalise, free in your browser
N
POST /verify/url$0.002✅ ValidationAPI
Screen a link for danger
check URLs before the click
N
POST /verify/url-safe$0.002✅ ValidationAPI
Detect phishing
score an email or page for red flags
N
POST /verify/phishing$0.003✅ ValidationFree
Detect injection attacks
flag SQLi and XSS in your browser
N
POST /verify/injection$0.002✅ ValidationFree
Check password strength
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N
POST /verify/password$0.002✅ ValidationAPI
Validate a postal address
parse and correct
N
POST /verify/address$0.003✅ ValidationFree
Check a postal code
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N
POST /verify/postal-code$0.002✅ ValidationFree
Validate a barcode
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N
POST /verify/barcode$0.002✅ ValidationFree
Parse a user agent
browser, OS and device, in your browser
N
POST /verify/user-agent$0.002✅ ValidationFree
Color contrast checker
test WCAG AA and AAA in your browser
G
POST /verify/color-contrast$0.002⚙️ Developer UtilitiesFree
Generate a UUID
v4, v7 or ULID, free in your browser
N
POST /dev/uuid$0.002⚙️ Developer UtilitiesFree
Hash a string
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N
POST /dev/hash$0.002⚙️ Developer UtilitiesFree
Sign and verify a payload
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N
POST /dev/hmac$0.002⚙️ Developer UtilitiesFree
Decode a JWT
read the claims and verify the signature
N
POST /dev/jwt-decode$0.002⚙️ Developer UtilitiesFree
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N
POST /dev/jwt-sign$0.002⚙️ Developer UtilitiesFree
Generate a 2FA code
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N
POST /dev/totp$0.002⚙️ Developer UtilitiesFree
Encrypt text
AES-256-GCM, your key, never stored
N
POST /dev/encrypt$0.002⚙️ Developer UtilitiesFree
Generate a password
strong and random, free in browser
N
POST /dev/password-gen$0.002⚙️ Developer UtilitiesFree
Encode and decode Base64
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N
POST /dev/base64$0.002⚙️ Developer UtilitiesFree
Encode and decode a URL
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N
POST /dev/url-encode$0.002⚙️ Developer UtilitiesFree
Make a URL slug
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N
POST /dev/slug$0.002⚙️ Developer UtilitiesFree
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N
POST /dev/timezone$0.002⚙️ Developer UtilitiesFree
Convert a Unix timestamp
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N
POST /dev/epoch$0.002⚙️ Developer UtilitiesFree
Count business days
with holidays for 100+ countries
N
POST /dev/business-days$0.002⚙️ Developer UtilitiesFree
Explain a cron expression
in plain words, free
N
POST /dev/cron-explain$0.002⚙️ Developer UtilitiesFree
See the next cron runs
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N
POST /dev/cron-next$0.002⚙️ Developer UtilitiesAPI
Schedule a webhook
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N
POST /dev/cron-webhook$0.002⚙️ Developer UtilitiesAPI
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in 30 minutes or 30 days
N
POST /dev/delay$0.002⚙️ Developer UtilitiesAPI
Shorten a link
on your own domain, published price
N
POST /dev/short-url$0.002⚙️ Developer UtilitiesAPI
Track link clicks
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N
POST /dev/short-url-stats$0.002⚙️ Developer UtilitiesFree
Make a QR code
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N
POST /dev/qr-generate$0.002⚙️ Developer UtilitiesFree
Add a logo to a QR code
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N
POST /dev/qr-logo$0.002⚙️ Developer UtilitiesAPI
Edit a QR after printing
change where it points, priced
N
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N
POST /dev/qr-decode$0.002⚙️ Developer UtilitiesFree
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N
POST /dev/barcode-generate$0.002⚙️ Developer UtilitiesAPI
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N
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N
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N
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N
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Generate a regex
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N
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Explain a regex
understand the pattern you inherited
N
POST /dev/regex-explain$0.003⚙️ Developer UtilitiesAPI
Explain code
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N
POST /dev/code-explain$0.003⚙️ Developer UtilitiesAPI
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N
POST /dev/code-document$0.003⚙️ Developer UtilitiesAPI
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N
POST /dev/text-to-sql$0.003⚙️ Developer UtilitiesAPI
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N
POST /dev/json-schema-gen$0.003⚙️ Developer UtilitiesAPI
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including the edge cases you forgot
N
POST /dev/unit-tests$0.003⚙️ Developer UtilitiesAPI
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conventional commits from a diff
N
POST /dev/commit-message$0.003⚙️ Developer UtilitiesAPI
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N
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N
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N
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N
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N
POST /dev/lorem$0.003⚙️ Developer UtilitiesFree
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N
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POST /dev/url-clean$0.002⚙️ Developer UtilitiesFree
Date difference and age calculator
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Regex tester
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A
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P
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Percentage calculator
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A
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A
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A
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A
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A
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A
POST /dev/sleep-calculator$0.002⚙️ Developer UtilitiesFree
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A
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A
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A
POST /dev/salary-calculator$0.002⚙️ Developer UtilitiesFree
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A
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A
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A
POST /dev/circle$0.002⚙️ Developer UtilitiesFree
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A
POST /dev/ohm-law$0.002⚙️ Developer UtilitiesFree
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A
POST /dev/one-rep-max$0.002⚙️ Developer UtilitiesFree
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A
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Simple interest calculator
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A
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A
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Discount calculator
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P
POST /dev/discount-calculator$0.002⚙️ Developer UtilitiesFree
Time calculator
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P
POST /dev/time-calculator$0.002⚙️ Developer UtilitiesFree
Body fat calculator
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A
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A
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A
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A
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A
POST /dev/gpa-calculator$0.002⚙️ Developer UtilitiesFree
Heart rate zones
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A
POST /dev/heart-rate-zones$0.002⚙️ Developer UtilitiesFree
Ideal weight calculator
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A
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Ovulation calculator
free online
A
POST /dev/ovulation-calculator$0.002⚙️ Developer UtilitiesFree
Speed distance time calculator
free
A
POST /dev/speed-distance-time$0.002⚙️ Developer UtilitiesFree
Water intake calculator
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A
POST /dev/water-intake$0.002⚙️ Developer UtilitiesFree
Fuel cost calculator
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P
POST /dev/fuel-cost$0.002⚙️ Developer UtilitiesFree
chmod calculator
rwx to octal free in your browser
P
POST /dev/chmod-calculator$0.002⚙️ Developer UtilitiesFree
Quadratic equation solver
roots free in your browser
P
POST /dev/quadratic-equation$0.002⚙️ Developer UtilitiesFree
Pythagorean theorem calculator
free in your browser
S
POST /dev/pythagoras$0.002⚙️ Developer UtilitiesFree
EV charge time calculator
free online
A
POST /dev/ev-charge-time$0.002⚙️ Developer UtilitiesFree
Inflation calculator
free online
A
POST /dev/inflation-calculator$0.002⚙️ Developer UtilitiesFree
A1C converter
educational ADA free
A
POST /dev/a1c-converter$0.002⚙️ Developer UtilitiesFree
BAC calculator
educational estimate, free online
A
POST /dev/bac-calculator$0.002⚙️ Developer UtilitiesFree
Dew point calculator
free online
A
POST /dev/dew-point$0.002⚙️ Developer UtilitiesFree
Heat index calculator
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A
POST /dev/heat-index$0.002⚙️ Developer UtilitiesFree
Macro calculator
protein carbs fat free
A
POST /dev/macro-calculator$0.002⚙️ Developer UtilitiesFree
Moon phase calculator
free online
A
POST /dev/moon-phase$0.002⚙️ Developer UtilitiesFree
Plate calculator
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A
POST /dev/plate-calculator$0.002⚙️ Developer UtilitiesFree
Tire size calculator
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A
POST /dev/tire-size$0.002⚙️ Developer UtilitiesFree
Permutation & combination calculator
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P
POST /dev/permutation-combination$0.002⚙️ Developer UtilitiesFree
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P
POST /dev/resistor-color-code$0.002⚙️ Developer UtilitiesFree
ROI calculator
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P
POST /dev/roi$0.002⚙️ Developer UtilitiesFree
Bell number calculator
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A
POST /math/bell-number$0.002⚙️ Developer UtilitiesFree
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A
POST /math/equilateral-triangle$0.002⚙️ Developer UtilitiesFree
Euler triangle OI distance calculator
free
A
POST /math/euler-triangle-formula$0.002⚙️ Developer UtilitiesFree
Intersecting chords calculator
free
A
POST /math/intersecting-chords$0.002⚙️ Developer UtilitiesFree
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free
A
POST /math/jacobsthal-number$0.002⚙️ Developer UtilitiesFree
Oblique cylinder calculator
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A
POST /math/oblique-cylinder$0.002⚙️ Developer UtilitiesFree
Spherical excess calculator
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A
POST /math/spherical-excess$0.002⚙️ Developer UtilitiesFree
Subfactorial calculator
free
A
POST /math/subfactorial$0.002⚙️ Developer UtilitiesFree
Torus sector calculator
free
A
POST /math/torus-sector$0.002⚙️ Developer UtilitiesFree
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free
A
POST /math/tribonacci-number$0.002⚙️ Developer UtilitiesFree
Trirectangular tetrahedron calculator
free
A
POST /math/trirectangular-tetrahedron$0.002⚙️ Developer UtilitiesFree
Break even occupancy calculator
free
A
POST /finance/break-even-occupancy$0.002⚙️ Developer UtilitiesFree
Capital gains tax estimator
free
A
POST /finance/capital-gains-tax$0.002⚙️ Developer UtilitiesFree
DSCR calculator
free
A
POST /finance/debt-service-coverage$0.002⚙️ Developer UtilitiesFree
FHA MIP calculator
free
A
POST /finance/fha-mip$0.002⚙️ Developer UtilitiesFree
FIRE number calculator
free
A
POST /finance/fire-number$0.002⚙️ Developer UtilitiesFree
Hard money loan calculator
free
A
POST /finance/hard-money-loan$0.002⚙️ Developer UtilitiesFree
Interest capitalization calculator
free
A
POST /finance/interest-capitalization$0.002⚙️ Developer UtilitiesFree
Mortgage recast calculator
free
A
POST /finance/mortgage-recast$0.002⚙️ Developer UtilitiesFree
One percent rule calculator
free
A
POST /finance/one-percent-rule$0.002⚙️ Developer UtilitiesFree
Rule of 78 rebate calculator
free
A
POST /finance/rule-of-78-rebate$0.002⚙️ Developer UtilitiesFree
SS claim breakeven calculator
free
A
POST /finance/ss-claim-breakeven$0.002⚙️ Developer UtilitiesFree
French Republican calendar
free
A
POST /date/french-republican$0.002⚙️ Developer UtilitiesFree
Interval intersection
free
A
POST /date/interval-intersection$0.002⚙️ Developer UtilitiesFree
Juche era converter
free
A
POST /date/juche$0.002⚙️ Developer UtilitiesFree
Julian ↔ Gregorian converter
free
S
POST /date/julian-calendar$0.002⚙️ Developer UtilitiesFree
Leap seconds UTC↔TAI
free
S
POST /date/leap-seconds$0.002⚙️ Developer UtilitiesFree
NTP ↔ Unix timestamp
free
S
POST /date/ntp-timestamp$0.002⚙️ Developer UtilitiesFree
Parse relative dates
free
S
POST /date/relative-parse$0.002⚙️ Developer UtilitiesFree
Roman Kalends/Nones/Ides
free
S
POST /date/roman-date$0.002⚙️ Developer UtilitiesFree
UUID v1/v6/v7 to timestamp
free
S
POST /date/uuid-time$0.002⚙️ Developer UtilitiesFree
Weekday occurrence in month
free
S
POST /date/weekday-occurrence$0.002⚙️ Developer UtilitiesFree
Sphere calculator
volume and surface free in your browser
S
POST /dev/sphere$0.002⚙️ Developer UtilitiesFree
Voltage divider calculator
free in your browser
S
POST /dev/voltage-divider$0.002⚙️ Developer UtilitiesFree
Polygon apothem calculator
free
A
POST /math/polygon-apothem$0.002⚙️ Developer UtilitiesFree
Taxable equivalent yield calculator
free online
A
POST /finance/taxable-equivalent-yield$0.002⚙️ Developer UtilitiesFree
Abjad numeral converter free online
S
POST /math/abjad-numerals$0.002⚙️ Developer UtilitiesFree
Age ratio calculator
present and future ages free
S
POST /math/age-ratio$0.002⚙️ Developer UtilitiesFree
Boat and stream speed calculator free online
S
POST /math/boat-stream$0.002⚙️ Developer UtilitiesFree
CP SP MP calculator
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S
POST /math/cp-sp-mp$0.002⚙️ Developer UtilitiesFree
Hebrew numeral converter and gematria free
A
POST /math/hebrew-numerals$0.002⚙️ Developer UtilitiesFree
Largest remainder seat allocation free
S
POST /math/largest-remainder$0.002⚙️ Developer UtilitiesFree
Maya vigesimal numeral converter free
P
POST /math/maya-numerals$0.002⚙️ Developer UtilitiesFree
Pie chart angles from values free online
S
POST /math/pie-chart-angles$0.002⚙️ Developer UtilitiesFree
Pipes and cisterns calculator free online
A
POST /math/pipes-cisterns$0.002⚙️ Developer UtilitiesFree
Sainte-Laguë seat allocation calculator free
S
POST /math/sainte-lague$0.002⚙️ Developer UtilitiesFree
Orthodox Christmas date
free
A
POST /date/orthodox-christmas$0.002⚙️ Developer UtilitiesFree
Victoria Day (Canada) date
free
A
POST /date/victoria-day-ca$0.002⚙️ Developer UtilitiesFree
Week of month calculator
free
A
POST /date/week-of-month$0.002⚙️ Developer UtilitiesFree
CD early withdrawal penalty
free
A
POST /finance/cd-early-penalty$0.002⚙️ Developer UtilitiesFree
Lease buyout cost
free
A
POST /finance/lease-buyout-cost$0.002⚙️ Developer UtilitiesFree
Mortgage offset account savings
free
A
POST /finance/mortgage-offset$0.002⚙️ Developer UtilitiesFree
Negative equity roll-in
free
A
POST /finance/negative-equity-rollin$0.002⚙️ Developer UtilitiesFree
Mortgage points break-even
free
A
POST /finance/points-breakeven$0.002⚙️ Developer UtilitiesFree
Prepayment penalty calculator
free
A
POST /finance/prepayment-penalty$0.002⚙️ Developer UtilitiesFree
Quarterly estimated tax
free
A
POST /finance/quarterly-estimated-tax$0.002⚙️ Developer UtilitiesFree
Standard vs itemized deduction
free
A
POST /finance/standard-vs-itemized$0.002⚙️ Developer UtilitiesFree
Gall–Peters projection calculator
free
A
POST /geo/gall-peters$0.002⚙️ Developer UtilitiesFree
Geocentric radius calculator
free
A
POST /geo/geocentric-radius$0.002⚙️ Developer UtilitiesFree
Vertical sextant angle distance
free
A
POST /geo/vertical-sextant-angle$0.002⚙️ Developer UtilitiesFree
Arithmetico-geometric series sum
free
A
POST /math/arithmetico-geometric-series$0.002⚙️ Developer UtilitiesFree
Chain discount / net price factor
free
A
POST /math/chain-discount$0.002⚙️ Developer UtilitiesFree
Hexagonal prism calculator
free
A
POST /math/hexagonal-prism$0.002⚙️ Developer UtilitiesFree
Markdown percentage calculator
free
A
POST /math/markdown-percent$0.002⚙️ Developer UtilitiesFree
Motzkin number calculator
free
A
POST /math/motzkin-number$0.002⚙️ Developer UtilitiesFree
Power of a point calculator
free
A
POST /math/power-of-a-point$0.002⚙️ Developer UtilitiesFree
Regular tetrahedron calculator
free
A
POST /math/regular-tetrahedron$0.002⚙️ Developer UtilitiesFree
Roman chronogram calculator
free
A
POST /math/roman-chronogram$0.002⚙️ Developer UtilitiesFree
Square pyramid calculator
free
A
POST /math/square-pyramid$0.002⚙️ Developer UtilitiesFree
Stair rise and run calculator
free
A
POST /math/stairs-rise-run$0.002⚙️ Developer UtilitiesFree
Tangent-secant theorem calculator
free
A
POST /math/tangent-secant-theorem$0.002⚙️ Developer UtilitiesFree
Wastage allowance calculator
free
A
POST /math/wastage-allowance$0.002⚙️ Developer UtilitiesFree
Hedges g effect size
free
A
POST /stat/hedges-g$0.002⚙️ Developer UtilitiesFree
Matthews correlation (MCC)
free
A
POST /stat/matthews-corr$0.002⚙️ Developer UtilitiesFree
Haversine distance - great-circle km, mi and m between two points
A
POST /geo/haversine$0.002⚙️ Developer UtilitiesFree
Absolute value equation solver
solve |ax+b|=c for x
S
POST /algebra/absolute-value-equation$0.002⚙️ Developer UtilitiesFree
Finite series partial sum
accumulate terms, free
S
POST /algebra/partial-sum-series$0.002⚙️ Developer UtilitiesFree
2×2 system by substitution
isolate, solve, free
S
POST /algebra/system-2x2-substitution$0.002⚙️ Developer UtilitiesFree
Kepler's third law calculator
find period or radius from a known orbit
A
POST /astro/kepler-third-law$0.002⚙️ Developer UtilitiesFree
Physical size from angular diameter
small-angle calculator
A
POST /astro/physical-size-from-angular$0.002⚙️ Developer UtilitiesFree
Propellant mass fraction calculator
delta-v and exhaust velocity
A
POST /astro/propellant-mass-fraction$0.002⚙️ Developer UtilitiesFree
Limiting reactant calculator
which reactant runs out first
A
POST /chem/limiting-reactant$0.002⚙️ Developer UtilitiesFree
Moles of product calculator
reactant moles and mole ratio
A
POST /chem/moles-of-product$0.002⚙️ Developer UtilitiesFree
Electrolysis overpotential calculator
applied vs thermodynamic voltage
A
POST /chem/overpotential$0.002⚙️ Developer UtilitiesFree
Percent yield calculator
actual over theoretical yield
A
POST /chem/percent-yield$0.002⚙️ Developer UtilitiesFree
Darken a hex color by percentage
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P
POST /color/darken$0.002⚙️ Developer UtilitiesFree
RGB to CMYK converter
print percentages, free online
P
POST /color/rgb-cmyk$0.002⚙️ Developer UtilitiesFree
Binomial coefficients row
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S
POST /combo/binomial-row$0.002⚙️ Developer UtilitiesFree
Decibel ratio converter
dB to power or amplitude linear ratio
P
POST /conv/decibel-ratio$0.002⚙️ Developer UtilitiesFree
Electrical conductivity converter
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P
POST /conv/electrical-conductivity$0.002⚙️ Developer UtilitiesFree
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P
POST /conv/equivalent-dose$0.002⚙️ Developer UtilitiesFree
HP to kW converter
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P
POST /conv/hp-to-kw$0.002⚙️ Developer UtilitiesFree
Length converter
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P
POST /conv/length$0.002⚙️ Developer UtilitiesFree
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P
POST /conv/moment-of-inertia$0.002⚙️ Developer UtilitiesFree
Pressure gradient converter
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POST /conv/pressure-gradient$0.002⚙️ Developer UtilitiesFree
Stone to lbs converter
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POST /conv/stone-to-lbs$0.002⚙️ Developer UtilitiesFree
Temperature converter
Celsius, Fahrenheit, Kelvin, Rankine
P
POST /conv/temperature$0.002⚙️ Developer UtilitiesFree
Add working days to a date
skip weekends, free
A
POST /date/add-workdays$0.002⚙️ Developer UtilitiesFree
US daylight saving start date
second Sunday of March, free
A
POST /date/daylight-saving-start-us$0.002⚙️ Developer UtilitiesFree
Days elapsed in the quarter
count whole days from quarter start
A
POST /date/days-elapsed-quarter$0.002⚙️ Developer UtilitiesFree
Easter Sunday date
Gregorian computus for any year
A
POST /date/easter$0.002⚙️ Developer UtilitiesFree
Generation by birth year
Millennial, Gen Z, Boomer and more
A
POST /date/generation-cohort$0.002⚙️ Developer UtilitiesFree
Battery runtime from Ah
capacity, load current, and usable DoD
A
POST /elec/battery-runtime-ah$0.002⚙️ Developer UtilitiesFree
Capacitor voltage rating selector
derate working voltage to a standard rating
A
POST /elec/capacitor-voltage-rating$0.002⚙️ Developer UtilitiesFree
Drift velocity calculator
find vd from current, n, A and q
A
POST /elec/drift-velocity$0.002⚙️ Developer UtilitiesFree
Transformer turns ratio calculator
Np/Ns and voltages, free
A
POST /elec/transformer-turns$0.002⚙️ Developer UtilitiesFree
Damm check digit
compute and validate, catch typos free
P
POST /enc/damm$0.002⚙️ Developer UtilitiesFree
Keyword substitution cipher
encrypt & decrypt online, free
P
POST /enc/keyword-cipher$0.002⚙️ Developer UtilitiesFree
Scytale cipher
encrypt or decrypt with a column transposition
P
POST /enc/scytale$0.002⚙️ Developer UtilitiesFree
encodeURIComponent tool
encode and decode URI components, free
P
POST /enc/url-component$0.002⚙️ Developer UtilitiesFree
UTF-16 code unit converter
encode or decode hex, free
P
POST /enc/utf16$0.002⚙️ Developer UtilitiesFree
Octal to decimal converter
base-8 string to integer, free
P
POST /fmt/octal-decimal$0.002⚙️ Developer UtilitiesFree
Cardinal to ordinal number converter
1st, 2nd, 3rd, free
P
POST /fmt/ordinal$0.002⚙️ Developer UtilitiesFree
Initial bearing calculator
forward azimuth between two coordinates
A
POST /geo/bearing$0.002⚙️ Developer UtilitiesFree
Crosswind component calculator
wind speed and angle, free
A
POST /geo/crosswind-component$0.002⚙️ Developer UtilitiesFree
Geohash encoder
latitude and longitude to a compact string
A
POST /geo/geohash-encode$0.002⚙️ Developer UtilitiesFree
Geographic midpoint calculator
great-circle halfway point free
A
POST /geo/midpoint$0.002⚙️ Developer UtilitiesFree
Geographic polygon perimeter
great-circle length of a lat/lon ring
A
POST /geo/polygon-perimeter$0.002⚙️ Developer UtilitiesFree
Pythagorean equirectangular distance
approximate ground metres between two points
A
POST /geo/pythagorean-geo-distance$0.002⚙️ Developer UtilitiesFree
Capsule volume & surface area
stadium of revolution, free
S
POST /geom/capsule$0.002⚙️ Developer UtilitiesFree
Hyperbola eccentricity
from semi-axes a and b, free
S
POST /geom/hyperbola-eccentricity$0.002⚙️ Developer UtilitiesFree
Polygon interior angle calculator
sum, exterior & per-angle
S
POST /geom/polygon-interior-angle$0.002⚙️ Developer UtilitiesFree
Star polygon area calculator
regular {n/d} area from points, density, radius
S
POST /geom/star-polygon-area$0.002⚙️ Developer UtilitiesFree
Triangle incenter calculator
incenter and inradius from vertices
S
POST /geom/triangle-incenter$0.002⚙️ Developer UtilitiesFree
Mifflin-St Jeor BMR calculator
basal metabolic rate from weight, height, age and sex
A
POST /health/bmr-mifflin$0.002⚙️ Developer UtilitiesFree
Caffeine dose by body weight
mg from mg/kg target, free
A
POST /health/caffeine-per-kg$0.002⚙️ Developer UtilitiesFree
eGFR kidney function calculator
CKD-EPI creatinine free
A
POST /health/egfr$0.002⚙️ Developer UtilitiesFree
Fat mass from body fat %
convert weight and percent to kg
A
POST /health/fat-mass-from-percent$0.002⚙️ Developer UtilitiesFree
Ponderal index calculator
mass over height cubed, free
A
POST /health/ponderal-index$0.002⚙️ Developer UtilitiesFree
Metronome subdivision calculator
duration in ms and frequency from tempo
A
POST /hobby/metronome-subdivision$0.002⚙️ Developer UtilitiesFree
Home circuit count calculator
lighting & outlets from sq ft
A
POST /home/circuit-count$0.002⚙️ Developer UtilitiesFree
Metal roofing panel calculator
panels from roof area and overlap
A
POST /home/metal-roofing-panels$0.002⚙️ Developer UtilitiesFree
Sod calculator
rolls and pallets from lawn area and waste
A
POST /home/sod$0.002⚙️ Developer UtilitiesFree
Harmonic series calculator
n-th partial sum H_n
S
POST /math/harmonic-series$0.002⚙️ Developer UtilitiesFree
Prime factorization
break any integer into primes and exponents
S
POST /math/prime-factorization$0.002⚙️ Developer UtilitiesFree
Projectile range calculator
speed, angle and gravity, free
A
POST /mech/projectile-range$0.002⚙️ Developer UtilitiesFree
Time of flight calculator
projectile launch speed, angle, gravity
A
POST /mech/projectile-time-of-flight$0.002⚙️ Developer UtilitiesFree
Simple pendulum period
T = 2π√(L/g) online
A
POST /mech/simple-pendulum$0.002⚙️ Developer UtilitiesFree
Flywheel spin-down time
inertia, speed, and braking torque
A
POST /mech/spin-down-time$0.002⚙️ Developer UtilitiesFree
List all ordered compositions of an integer
free
S
POST /numth/compositions-list$0.002⚙️ Developer UtilitiesFree
Discrete logarithm solver
baby-step giant-step mod p
S
POST /numth/discrete-log$0.002⚙️ Developer UtilitiesFree
Divisors of a number
list, count and sum, free
S
POST /numth/divisor-list$0.002⚙️ Developer UtilitiesFree
Is prime checker
trial division and Miller–Rabin, free
S
POST /numth/prime-checker$0.002⚙️ Developer UtilitiesFree
Acoustic resonance Q factor calculator
f0 over half-power bandwidth
A
POST /optics/acoustic-resonance-q-factor$0.002⚙️ Developer UtilitiesFree
Lensmaker's equation
focal length from n, R1, R2
A
POST /optics/lensmaker$0.002⚙️ Developer UtilitiesFree
Wavelength calculator
speed divided by frequency, free
A
POST /phys/wavelength$0.002⚙️ Developer UtilitiesFree
Durbin-Watson statistic calculator
first-order residual autocorrelation
S
POST /stat/durbin-watson$0.002⚙️ Developer UtilitiesFree
Tukey HSD post-hoc
pairwise comparisons after ANOVA, free
S
POST /stat/tukey-hsd$0.002⚙️ Developer UtilitiesFree
Reverse line order
flip text lines top to bottom, free
P
POST /str/reverse-lines$0.002⚙️ Developer UtilitiesFree
Charles's law calculator
find V2 or T2 at constant pressure
A
POST /thermo/charles-law$0.002⚙️ Developer UtilitiesFree
EV trip charging cost
distance, efficiency, and electricity price
A
POST /travel/ev-trip-cost$0.002⚙️ Developer UtilitiesFree
Half-angle calculator
sin, cos, tan of half the angle with correct signs
S
POST /trig/half-angle$0.002⚙️ Developer UtilitiesFree
Rectangular to polar converter
r and theta in the correct quadrant
S
POST /trig/rectangular-to-polar$0.002⚙️ Developer UtilitiesFree
Midline of a sinusoidal function
find y = D from the vertical shift
S
POST /trig/sinusoid-midline$0.002⚙️ Developer UtilitiesFree
EMC field strength converter
V/m, dBµV/m, A/m, free
A
POST /conv/emc-field-strength$0.002⚙️ Developer UtilitiesFree
First-order reaction time calculator
t = ln([A]₀/[A])/k, free
S
POST /chem/first-order-time$0.002⚙️ Developer UtilitiesFree
Absorbed dose converter
Gy, mGy, rad and erg/g, free
P
POST /conv/absorbed-dose$0.002⚙️ Developer UtilitiesFree
Acceleration converter
m/s², ft/s², g and gal, free
A
POST /conv/acceleration$0.002⚙️ Developer UtilitiesFree
Mole unit converter
mol, mmol, µmol, kmol and lb-mol, free
A
POST /conv/amount-of-substance$0.002⚙️ Developer UtilitiesFree
Angle converter
degrees, radians, gradians, turns, free
P
POST /conv/angle$0.002⚙️ Developer UtilitiesFree
Angular acceleration converter
rad/s², deg/s² and rev/min², free
A
POST /conv/angular-acceleration$0.002⚙️ Developer UtilitiesFree
Angular velocity converter
rad/s, deg/s, RPM, RPS free
S
POST /conv/angular-velocity$0.002⚙️ Developer UtilitiesFree
Area converter
m², ft², acres, hectares, mi², km² free
S
POST /conv/area$0.002⚙️ Developer UtilitiesFree
Astronomical distance converter
AU, ly, pc, km, mi, free
P
POST /conv/astronomical-distance$0.002⚙️ Developer UtilitiesFree
Blood glucose converter
mg/dL ↔ mmol/L free
S
POST /conv/blood-glucose$0.002⚙️ Developer UtilitiesFree
Bra size converter
US, UK, EU, French & Australian sizes, free
S
POST /conv/bra-size$0.002⚙️ Developer UtilitiesFree
Capacitance converter
farads, millifarads, microfarads, picofarads, free
A
POST /conv/capacitance$0.002⚙️ Developer UtilitiesFree
Catalytic activity converter
katal, µkat, nkat and enzyme units (U), free
P
POST /conv/catalytic-activity$0.002⚙️ Developer UtilitiesFree
Cholesterol unit converter
mg/dL ↔ mmol/L for total, HDL and LDL, free
A
POST /conv/cholesterol$0.002⚙️ Developer UtilitiesFree
Clothing size converter
US, UK, EU and S/M/L, free
A
POST /conv/clothing-size$0.002⚙️ Developer UtilitiesFree
Molar concentration converter
mol/L, mmol/L, µmol/L, mol/m³ free
S
POST /conv/concentration$0.002⚙️ Developer UtilitiesFree
Conductance converter
siemens, millisiemens, microsiemens, free
A
POST /conv/conductance$0.002⚙️ Developer UtilitiesFree
Data transfer rate converter
bps, Mbps, MB/s, free
A
POST /conv/data-rate$0.002⚙️ Developer UtilitiesFree
Digital storage converter
bytes, KB, MB, GB, TB, KiB, MiB free
S
POST /conv/data-size$0.002⚙️ Developer UtilitiesFree
Density converter
kg/m³, g/cm³, lb/ft³ and lb/gal, free
A
POST /conv/density$0.002⚙️ Developer UtilitiesFree
Dynamic viscosity converter
Pa·s, poise, cP, lbf·s/ft² free
S
POST /conv/dynamic-viscosity$0.002⚙️ Developer UtilitiesFree
Electric charge converter
C, mC, µC, Ah, mAh, e free
S
POST /conv/electric-charge$0.002⚙️ Developer UtilitiesFree
Electric current converter
A, mA, µA, kA, abA, free
A
POST /conv/electric-current$0.002⚙️ Developer UtilitiesFree
Electric field strength converter
V/m, V/cm, kV/m, V/mil, free
P
POST /conv/electric-field$0.002⚙️ Developer UtilitiesFree
Energy converter
joules, calories, kWh, BTU, eV, free
A
POST /conv/energy$0.002⚙️ Developer UtilitiesFree
Fahrenheit to Celsius converter
exact (F−32)×5/9, free
P
POST /conv/fahrenheit-to-celsius$0.002⚙️ Developer UtilitiesFree
Volume flow rate converter
L/s, m³/h, GPM, CFM, free
A
POST /conv/flow-rate$0.002⚙️ Developer UtilitiesFree
Force converter
newtons, kN, dynes, lbf, kgf, poundals, free
A
POST /conv/force$0.002⚙️ Developer UtilitiesFree
Frequency converter
Hz, kHz, MHz, GHz, RPM, rad/s free
S
POST /conv/frequency$0.002⚙️ Developer UtilitiesFree
Frequency wavelength converter
f ↔ λ with c or custom speed, free
S
POST /conv/frequency-wavelength$0.002⚙️ Developer UtilitiesFree
Fuel economy converter
MPG US, MPG imperial, km/L and L/100km, free
A
POST /conv/fuel-economy$0.002⚙️ Developer UtilitiesFree
Fuel price unit converter
US gal, imperial gal, liter, free
A
POST /conv/fuel-price$0.002⚙️ Developer UtilitiesFree
Grain weight converter
grains, grams, milligrams, ounces, free
A
POST /conv/grain-weight$0.002⚙️ Developer UtilitiesFree
Hat size converter
US fitted, UK, EU cm, head circumference, free
A
POST /conv/hat-size$0.002⚙️ Developer UtilitiesFree
Heat flux density converter
W/m², W/cm², BTU/(h·ft²), cal/(s·cm²), free
A
POST /conv/heat-flux$0.002⚙️ Developer UtilitiesFree
Heat transfer coefficient converter
W/(m²·K), BTU/(h·ft²·°F), free
S
POST /conv/heat-transfer-coefficient$0.002⚙️ Developer UtilitiesFree
Illuminance converter
lux, foot-candles, phot, lm/m² free
S
POST /conv/illuminance$0.002⚙️ Developer UtilitiesFree
Inductance converter
H, mH, µH, nH, pH, free
A
POST /conv/inductance$0.002⚙️ Developer UtilitiesFree
Gold karat converter
karats, fineness, purity %, free
P
POST /conv/karat-gold$0.002⚙️ Developer UtilitiesFree
Kinematic viscosity converter
m²/s, stokes, centistokes and ft²/s, free
A
POST /conv/kinematic-viscosity$0.002⚙️ Developer UtilitiesFree
Luminance converter
nit, stilb, lambert, foot-lambert and apostilb, free
A
POST /conv/luminance$0.002⚙️ Developer UtilitiesFree
Luminous flux converter
lm, mlm, µlm, klm, Mlm, free
P
POST /conv/luminous-flux$0.002⚙️ Developer UtilitiesFree
Luminous intensity converter
cd, mcd, kcd, candlepower, free
A
POST /conv/luminous-intensity$0.002⚙️ Developer UtilitiesFree
Magnetic flux converter
weber, milliweber, microweber, maxwell, free
A
POST /conv/magnetic-flux$0.002⚙️ Developer UtilitiesFree
Magnetic flux density converter
tesla, millitesla, gauss, Wb/m², free
A
POST /conv/magnetic-flux-density$0.002⚙️ Developer UtilitiesFree
Mass converter
kg, g, lb, oz, stone, tonne and mg, free
A
POST /conv/mass$0.002⚙️ Developer UtilitiesFree
Mass flow rate converter
kg/s, g/s, lb/h, t/h, free
A
POST /conv/mass-flow-rate$0.002⚙️ Developer UtilitiesFree
Molar mass converter
g/mol, kg/mol, kg/kmol, free
A
POST /conv/molar-mass$0.002⚙️ Developer UtilitiesFree
Momentum converter
kg·m/s, g·cm/s, lb·ft/s free
S
POST /conv/momentum$0.002⚙️ Developer UtilitiesFree
Running pace converter
min/km, min/mile, km/h and mph, free
A
POST /conv/pace$0.002⚙️ Developer UtilitiesFree
Paper size dimensions
ISO A B C, US Letter, Legal, Tabloid, free
A
POST /conv/paper-size$0.002⚙️ Developer UtilitiesFree
Paper weight converter
gsm ↔ lb for text, bond, cover, index
S
POST /conv/paper-weight$0.002⚙️ Developer UtilitiesFree
Power converter
W, kW, MW, hp, BTU/h, ft·lb/s free
S
POST /conv/power$0.002⚙️ Developer UtilitiesFree
PPM percent converter
ppm, ppb, percent and per-mille free
A
POST /conv/ppm$0.002⚙️ Developer UtilitiesFree
Radiation exposure converter
C/kg, roentgen, mR, free
A
POST /conv/radiation-exposure$0.002⚙️ Developer UtilitiesFree
Radioactivity converter
Bq, Ci, Rd and SI multiples, free
P
POST /conv/radioactivity$0.002⚙️ Developer UtilitiesFree
Electrical resistance converter
ohms, mΩ, kΩ, MΩ, GΩ free
S
POST /conv/resistance$0.002⚙️ Developer UtilitiesFree
Electrical resistivity converter
Ω·m, Ω·cm, μΩ·cm, Ω·cmil/ft free
S
POST /conv/resistivity$0.002⚙️ Developer UtilitiesFree
Ring size converter
US, UK, EU and diameter mm equivalents, free
A
POST /conv/ring-size$0.002⚙️ Developer UtilitiesFree
Roof pitch converter
rise-in-12, degrees and percent slope, free
A
POST /conv/roof-pitch$0.002⚙️ Developer UtilitiesFree
Shoe size converter
US, UK, EU and cm, men & women, free
P
POST /conv/shoe-size$0.002⚙️ Developer UtilitiesFree
Slope grade converter
percent grade, degrees and rise-over-run, free
A
POST /conv/slope-grade$0.002⚙️ Developer UtilitiesFree
Solid angle converter
steradians, deg², spat, sphere free
S
POST /conv/solid-angle$0.002⚙️ Developer UtilitiesFree
Sound pressure level converter
Pa ↔ dB SPL, free
A
POST /conv/sound-level$0.002⚙️ Developer UtilitiesFree
Specific energy converter
J/kg, kJ/kg, cal/g, BTU/lb, free
A
POST /conv/specific-energy$0.002⚙️ Developer UtilitiesFree
Specific heat capacity converter
J/(kg·K), cal/(g·°C), BTU/(lb·°F), free
P
POST /conv/specific-heat$0.002⚙️ Developer UtilitiesFree
Specific volume converter
m³/kg, L/kg, ft³/lb, free
A
POST /conv/specific-volume$0.002⚙️ Developer UtilitiesFree
Speed converter
m/s, km/h, mph, knots, ft/s, free
P
POST /conv/speed$0.002⚙️ Developer UtilitiesFree
Surface tension converter
N/m, mN/m, dyn/cm, lbf/ft, free
P
POST /conv/surface-tension$0.002⚙️ Developer UtilitiesFree
Thermal conductivity converter
W/(m·K), BTU/(h·ft·°F), cal/(s·cm·°C) free
S
POST /conv/thermal-conductivity$0.002⚙️ Developer UtilitiesFree
Thermal resistance converter
K/W, °C/W, °F·h/BTU, free
A
POST /conv/thermal-resistance$0.002⚙️ Developer UtilitiesFree
Time unit converter
seconds, minutes, hours, days, weeks, ms and µs, free
A
POST /conv/time$0.002⚙️ Developer UtilitiesFree
Torque converter
N·m, N·cm, lbf·ft, lbf·in, kgf·m, free
P
POST /conv/torque$0.002⚙️ Developer UtilitiesFree
Screen size converter
diagonal in/cm and W×H from aspect ratio, free
A
POST /conv/tv-size$0.002⚙️ Developer UtilitiesFree
Points to pixels converter
pt, px and picas at 96 DPI, free
A
POST /conv/typography-pt-px$0.002⚙️ Developer UtilitiesFree
PX to EM converter
CSS pixels ↔ em with base font size, free
S
POST /conv/typography-px-em$0.002⚙️ Developer UtilitiesFree
px to rem converter
CSS pixels ↔ rem with root font size
P
POST /conv/typography-px-rem$0.002⚙️ Developer UtilitiesFree
Voltage converter
V, mV, µV, kV, MV, free
P
POST /conv/voltage$0.002⚙️ Developer UtilitiesFree
Volume converter
liters, gallons, quarts, m³, ft³, free
A
POST /conv/volume$0.002⚙️ Developer UtilitiesFree
Water hardness converter
ppm, mg/L, gpg, °dH free
S
POST /conv/water-hardness$0.002⚙️ Developer UtilitiesFree
Wire gauge converter
AWG to mm, inches & area, free
P
POST /conv/wire-gauge$0.002⚙️ Developer UtilitiesFree
Complete the square calculator
vertex form a(x−h)²+k, free
S
POST /algebra/complete-the-square$0.002⚙️ Developer UtilitiesFree
Cross product calculator
3D vector a×b and parallelogram area, free
S
POST /algebra/cross-product$0.002⚙️ Developer UtilitiesFree
Exponent rules calculator
product, quotient, power, free
S
POST /algebra/exponent-rules$0.002⚙️ Developer UtilitiesFree
Linear inequality solver
ax+b ⊙ c for x, interval form, free
S
POST /algebra/inequality-solver$0.002⚙️ Developer UtilitiesFree
Matrix inverse calculator
Gauss-Jordan A⁻¹, free
S
POST /algebra/matrix-inverse$0.002⚙️ Developer UtilitiesFree
Matrix multiplication calculator
A×B product matrix, free
S
POST /algebra/matrix-multiply$0.002⚙️ Developer UtilitiesFree
Polynomial long division calculator
quotient and remainder, free
S
POST /algebra/polynomial-divide$0.002⚙️ Developer UtilitiesFree
Polynomial GCD calculator
Euclidean algorithm on coefficients, free
S
POST /algebra/polynomial-gcd$0.002⚙️ Developer UtilitiesFree
Reduced row echelon form calculator
Gauss-Jordan RREF, free
S
POST /algebra/rref$0.002⚙️ Developer UtilitiesFree
3×3 system of equations solver
Cramer's rule, free
S
POST /algebra/system-3x3$0.002⚙️ Developer UtilitiesFree
Absolute magnitude calculator
M from m and distance (pc), free
S
POST /astro/absolute-magnitude$0.002⚙️ Developer UtilitiesFree
Light travel time calculator
t = d/c from km or AU, free
S
POST /astro/light-travel-time$0.002⚙️ Developer UtilitiesFree
Planet density calculator
mean bulk density from M and R, free
S
POST /astro/planet-density$0.002⚙️ Developer UtilitiesFree
Schwarzschild radius calculator
Rs = 2GM/c² event horizon, free
S
POST /astro/schwarzschild-radius$0.002⚙️ Developer UtilitiesFree
Surface gravity calculator
g = G·M/R² in m/s², free
S
POST /astro/surface-gravity$0.002⚙️ Developer UtilitiesFree
Telescope resolution calculator
Rayleigh criterion θ=1.22λ/D, free
S
POST /astro/telescope-resolution$0.002⚙️ Developer UtilitiesFree
Arrhenius equation calculator
k = A·e^(−Ea/RT), free
S
POST /chem/arrhenius$0.002⚙️ Developer UtilitiesFree
Arrhenius temperature calculator
T from k, A, Ea, free
S
POST /chem/arrhenius-temperature$0.002⚙️ Developer UtilitiesFree
Average molecular speed calculator
v̄ = √(8RT/πM), free
S
POST /chem/average-molecular-speed$0.002⚙️ Developer UtilitiesFree
Average rate of reaction calculator
|Δc|/Δt from concentration, free
S
POST /chem/average-reaction-rate$0.002⚙️ Developer UtilitiesFree
Avogadro's law moles calculator
n₂ = n₁(V₂/V₁), free
S
POST /chem/avogadro-law-moles$0.002⚙️ Developer UtilitiesFree
Boiling point elevation calculator
ΔTb = i·Kb·m, free
S
POST /chem/boiling-point-elevation$0.002⚙️ Developer UtilitiesFree
Born-Haber lattice energy calculator
U from formation, sublimation, free
S
POST /chem/born-haber-cycle$0.002⚙️ Developer UtilitiesFree
Charles's law final volume calculator
V₂ = V₁(T₂/T₁), free
S
POST /chem/charles-final-volume$0.002⚙️ Developer UtilitiesFree
Vaporization enthalpy calculator
Clausius–Clapeyron ΔHvap from two, free
S
POST /chem/clausius-clapeyron-enthalpy$0.002⚙️ Developer UtilitiesFree
Combined gas law final volume calculator
V₂ = P₁V₁T₂/(P₂T₁), free
S
POST /chem/combined-gas-final-volume$0.002⚙️ Developer UtilitiesFree
Cryoscopic constant calculator
Kf = ΔTf/(i·m), free
S
POST /chem/cryoscopic-constant$0.002⚙️ Developer UtilitiesFree
Decay constant calculator
λ from half-life, free
S
POST /chem/decay-constant-half-life$0.002⚙️ Developer UtilitiesFree
Degree of dissociation calculator
α from van't Hoff factor i, free
S
POST /chem/degree-dissociation-from-i$0.002⚙️ Developer UtilitiesFree
Dilution factor calculator
DF = V_final/V_stock and fold dilution, free
S
POST /chem/dilution-factor$0.002⚙️ Developer UtilitiesFree
Degree of dissociation calculator
α from Kc and initial, free
S
POST /chem/dissociation-from-kc$0.002⚙️ Developer UtilitiesFree
Empirical formula from percent composition calculator
free
S
POST /chem/empirical-from-percent$0.002⚙️ Developer UtilitiesFree
Heat of formation from reaction calculator
unknown ΔH_f, free
S
POST /chem/enthalpy-of-formation-unknown$0.002⚙️ Developer UtilitiesFree
Molar enthalpy calculator
ΔH = Q/n from heat and moles, free
S
POST /chem/enthalpy-per-mole$0.002⚙️ Developer UtilitiesFree
Equilibrium constant from Gibbs calculator
K = exp(−ΔG°/RT), free
S
POST /chem/equilibrium-from-gibbs$0.002⚙️ Developer UtilitiesFree
Equilibrium yield calculator
percent of theoretical maximum at, free
S
POST /chem/equilibrium-yield$0.002⚙️ Developer UtilitiesFree
Formula units calculator
N = (m/M)·N_A from mass, free
S
POST /chem/formula-units$0.002⚙️ Developer UtilitiesFree
Fraction of molecules above Ea calculator
f = e^(−Ea/RT), free
S
POST /chem/fraction-molecules-above-ea$0.002⚙️ Developer UtilitiesFree
Freezing point depression calculator
ΔTf = i·Kf·m from molality, free
S
POST /chem/freezing-point-depression-molality$0.002⚙️ Developer UtilitiesFree
Fuel energy content calculator
E = m × energy density, free
S
POST /chem/fuel-energy-content$0.002⚙️ Developer UtilitiesFree
Effusion remaining fraction calculator
lighter gas left after, free
S
POST /chem/gas-leak-effusion-fraction$0.002⚙️ Developer UtilitiesFree
Gas stoichiometry volume calculator
product gas V from moles, free
S
POST /chem/gas-stoichiometry-volume$0.002⚙️ Developer UtilitiesFree
Gas volume at STP calculator
V = n × 22.4 L, free
S
POST /chem/gas-stp-volume$0.002⚙️ Developer UtilitiesFree
Gas temperature from P, V, n calculator
T = PV/nR (ideal gas), free
S
POST /chem/gas-temperature-from-ptv$0.002⚙️ Developer UtilitiesFree
Gas volume at NTP calculator
V = n × 24.0 L, free
S
POST /chem/gas-volume-at-ntp$0.002⚙️ Developer UtilitiesFree
Gibbs free energy calculator
ΔG = ΔH − TΔS from enthalpy, free
S
POST /chem/gibbs-from-enthalpy-entropy$0.002⚙️ Developer UtilitiesFree
Grams of product from moles calculator
n×MM in grams, free
S
POST /chem/grams-of-product-from-moles$0.002⚙️ Developer UtilitiesFree
Grams of solute for molarity calculator
M×V×MM in grams, free
S
POST /chem/grams-solute-for-molarity$0.002⚙️ Developer UtilitiesFree
Instantaneous rate from tangent calculator
|Δc|/Δt from two nearby, free
S
POST /chem/instantaneous-rate$0.002⚙️ Developer UtilitiesFree
Equilibrium constant at new temperature
van't Hoff K2 from K1, free
S
POST /chem/k-at-new-temperature$0.002⚙️ Developer UtilitiesFree
Kp from partial pressures calculator
equilibrium Kp = ∏P^ν, free
S
POST /chem/kp-from-partial-pressures$0.002⚙️ Developer UtilitiesFree
Ksp from solubility calculator
Ksp = ∏(νᵢ·s)^νᵢ from molar s, free
S
POST /chem/ksp-from-solubility$0.002⚙️ Developer UtilitiesFree
Le Chatelier pressure shift calculator
equilibrium vs pressure, free
S
POST /chem/le-chatelier-pressure-shift$0.002⚙️ Developer UtilitiesFree
Limiting reagent from masses calculator
two reactants, free
S
POST /chem/limiting-reactant-two$0.002⚙️ Developer UtilitiesFree
Mass percent to molality calculator
w/w % + MM → mol/kg, free
S
POST /chem/mass-percent-to-molality$0.002⚙️ Developer UtilitiesFree
Mass percent to ppm converter
% w/w → ppm & ppb, free
S
POST /chem/mass-percent-to-ppm$0.002⚙️ Developer UtilitiesFree
Mass to gas volume calculator
V = mRT/(MP) ideal gas, free
S
POST /chem/mass-to-gas-volume$0.002⚙️ Developer UtilitiesFree
Mass-to-mass stoichiometry calculator
product mass from reactant, free
S
POST /chem/mass-to-mass-stoich$0.002⚙️ Developer UtilitiesFree
mg/L to molarity calculator
concentration + molar mass → mol/L, free
S
POST /chem/mg-per-liter-to-molarity$0.002⚙️ Developer UtilitiesFree
Molar concentration calculator
c = n/V in mol/L, free
S
POST /chem/molar-concentration$0.002⚙️ Developer UtilitiesFree
Molar mass from boiling point elevation
M = Kb·g / (ΔTb·kg), free
S
POST /chem/molar-mass-from-bp-elevation$0.002⚙️ Developer UtilitiesFree
Molar mass from gas density calculator
M = ρRT/P (ideal gas), free
S
POST /chem/molar-mass-from-gas-density$0.002⚙️ Developer UtilitiesFree
Molarity from moles and volume calculator
M = n/V in mol/L, free
S
POST /chem/molarity-from-moles-volume$0.002⚙️ Developer UtilitiesFree
Molarity to molality calculator
M, density, MM → mol/kg, free
S
POST /chem/molarity-to-molality$0.002⚙️ Developer UtilitiesFree
Mole fraction to mass percent calculator
free binary conversion
S
POST /chem/mole-fraction-to-mass-percent$0.002⚙️ Developer UtilitiesFree
Osmolarity calculator
Osm = i·M in osmoles per liter, free
S
POST /chem/osmolarity$0.002⚙️ Developer UtilitiesFree
Oxygen for combustion calculator
moles O₂ for CₓHᵧ hydrocarbon, free
S
POST /chem/oxygen-required-combustion$0.002⚙️ Developer UtilitiesFree
Particles to moles calculator
n = N / N_A, free
S
POST /chem/particles-to-moles$0.002⚙️ Developer UtilitiesFree
Percent composition calculator
mass % from formula, free
S
POST /chem/percent-composition$0.002⚙️ Developer UtilitiesFree
Percent to molarity calculator
mass % + density → mol/L, free
S
POST /chem/percent-to-molarity$0.002⚙️ Developer UtilitiesFree
Percent water in hydrate calculator
mass % H₂O from hydrate &, free
S
POST /chem/percent-water-in-hydrate$0.002⚙️ Developer UtilitiesFree
Strong acid pH calculator
pH = −log₁₀(C) monoprotic, free
S
POST /chem/ph-strong-acid$0.002⚙️ Developer UtilitiesFree
PPB concentration calculator
parts per billion by mass, free
S
POST /chem/ppb-concentration$0.002⚙️ Developer UtilitiesFree
PPM from molarity calculator
M, molar mass, density → ppm, free
S
POST /chem/ppm-from-molarity$0.002⚙️ Developer UtilitiesFree
Equilibrium direction predictor
Q vs K shift direction, free
S
POST /chem/q-vs-k-direction$0.002⚙️ Developer UtilitiesFree
Rate constant from half-life calculator
k = ln(2)/t½, free
S
POST /chem/rate-constant-from-half-life$0.002⚙️ Developer UtilitiesFree
Graham's law calculator
relative effusion rate √(M₂/M₁), free
S
POST /chem/rate-of-effusion$0.002⚙️ Developer UtilitiesFree
Reaction order from rate data calculator
n = log(r₁/r₂)/log(c₁/c₂), free
S
POST /chem/reaction-order-from-rates$0.002⚙️ Developer UtilitiesFree
Solution boiling point calculator
Tb = T0 + i·Kb·m, free
S
POST /chem/solution-boiling-point$0.002⚙️ Developer UtilitiesFree
Specific heat from calorimetry calculator
c = Q/(m·ΔT), free
S
POST /chem/specific-heat-from-calorimetry$0.002⚙️ Developer UtilitiesFree
Stock solution volume calculator
V1 from C1, C2, V2 dilution, free
S
POST /chem/stock-solution-volume$0.002⚙️ Developer UtilitiesFree
Theoretical moles of product calculator
limiting moles × mole ratio, free
S
POST /chem/theoretical-moles-product$0.002⚙️ Developer UtilitiesFree
Theoretical yield from limiting reactant calculator
moles, free
S
POST /chem/theoretical-yield-from-limiting$0.002⚙️ Developer UtilitiesFree
Total ion concentration calculator
C = i·M from salt molarity, free
S
POST /chem/total-ion-concentration$0.002⚙️ Developer UtilitiesFree
Total pressure of gas mixture calculator
Dalton P = ΣPᵢ, free
S
POST /chem/total-pressure-gas-mixture$0.002⚙️ Developer UtilitiesFree
Van der Waals pressure calculator
P = nRT/(V−nb) − an²/V², free
S
POST /chem/van-der-waals-pressure$0.002⚙️ Developer UtilitiesFree
Vapor pressure molar mass calculator
M from relative lowering, free
S
POST /chem/vapor-pressure-molar-mass$0.002⚙️ Developer UtilitiesFree
Volume percent calculator
% v/v from solute and solution, free
S
POST /chem/volume-percent$0.002⚙️ Developer UtilitiesFree
Volume-to-volume gas stoichiometry calculator
V₂ from V₁ and coeffs, free
S
POST /chem/volume-to-volume-gas-stoich$0.002⚙️ Developer UtilitiesFree
Work of gas expansion calculator
W = −P_ext·ΔV, free
S
POST /chem/work-gas-expansion$0.002⚙️ Developer UtilitiesFree
Zero-order half-life calculator
t½ = [A]₀/(2k), free
S
POST /chem/zero-order-half-life$0.002⚙️ Developer UtilitiesFree
WCAG contrast ratio checker
AA/AAA for normal and large text
S
POST /color/contrast$0.002⚙️ Developer UtilitiesFree
RGB to hex converter
0–255 channels to #RRGGBB, free
S
POST /color/rgb-hex$0.002⚙️ Developer UtilitiesFree
RGB to HSV converter
0–255 channels to hue, saturation, value, free
S
POST /color/rgb-hsv$0.002⚙️ Developer UtilitiesFree
RGB to LAB converter
sRGB channels to CIE L*a*b* (D65), free
S
POST /color/rgb-lab$0.002⚙️ Developer UtilitiesFree
Color temperature to RGB
Kelvin 1000–40000 to sRGB, free
S
POST /color/temperature$0.002⚙️ Developer UtilitiesFree
Tetradic color scheme generator
four hues from one hex, free
S
POST /color/tetradic$0.002⚙️ Developer UtilitiesFree
Combinations with repetition
multiset C(n+r−1, r), free
S
POST /combo/combinations-with-repetition$0.002⚙️ Developer UtilitiesFree
Handshake problem calculator
n choose 2 and inverse, free
S
POST /combo/handshake$0.002⚙️ Developer UtilitiesFree
Monotone lattice paths on an a×b grid
C(a+b, a), free
S
POST /combo/lattice-paths$0.002⚙️ Developer UtilitiesFree
Unsigned Stirling numbers of the first kind
c(n,k) cycles, free
S
POST /combo/stirling-first$0.002⚙️ Developer UtilitiesFree
Butter measurement converter
sticks, tbsp, cups, grams free
S
POST /cook/butter$0.002⚙️ Developer UtilitiesFree
Cake tin size converter
round ↔ square by area, in & cm free
S
POST /cook/cake-tin$0.002⚙️ Developer UtilitiesFree
Honey cups to grams converter
tbsp & density free
S
POST /cook/honey$0.002⚙️ Developer UtilitiesFree
Pints to liters converter
US & imperial pint free
S
POST /cook/pints-liters$0.002⚙️ Developer UtilitiesFree
Teaspoons to ml converter
US & metric tsp free
S
POST /cook/tsp-ml$0.002⚙️ Developer UtilitiesFree
Add months to a date
shift calendar date with month-end clamp, free
S
POST /date/add-months$0.002⚙️ Developer UtilitiesFree
Birthstone by birth month
traditional and modern stones, free
S
POST /date/birthstone$0.002⚙️ Developer UtilitiesFree
Chinese zodiac sign calculator
animal by year and lunar New Year, free
S
POST /date/chinese-zodiac$0.002⚙️ Developer UtilitiesFree
Days between two dates
whole calendar day count, free
S
POST /date/days-between$0.002⚙️ Developer UtilitiesFree
Days elapsed in the year
days since January 1, free
S
POST /date/days-elapsed-year$0.002⚙️ Developer UtilitiesFree
Easter Sunday date calculator
Gregorian computus by year, free
S
POST /date/easter-sunday$0.002⚙️ Developer UtilitiesFree
Julian Day to date converter
Gregorian calendar from JDN, free
S
POST /date/from-julian-day$0.002⚙️ Developer UtilitiesFree
Golden number and epact calculator
ecclesiastical year numbers, free
S
POST /date/golden-number$0.002⚙️ Developer UtilitiesFree
ISO week number calculator
week and week-year from any date, free
S
POST /date/iso-week-number$0.002⚙️ Developer UtilitiesFree
ISO week to date converter
calendar date from week year, free
S
POST /date/iso-week-to-date$0.002⚙️ Developer UtilitiesFree
First and last day of month
calendar start and end dates, free
S
POST /date/month-start-end$0.002⚙️ Developer UtilitiesFree
Next leap year finder
next Gregorian leap year on or after a year, free
S
POST /date/next-leap-year$0.002⚙️ Developer UtilitiesFree
Next occurrence of a weekday
next Monday/Friday date from any day, free
S
POST /date/next-weekday$0.002⚙️ Developer UtilitiesFree
Subtract days from a date
earlier calendar date calculator, free
S
POST /date/subtract-days$0.002⚙️ Developer UtilitiesFree
Antenna length calculator
quarter-wave and half-wave from frequency, free
S
POST /elec/antenna-length$0.002⚙️ Developer UtilitiesFree
Battery runtime calculator
hours from Wh and load watts, free
S
POST /elec/battery-runtime-wh$0.002⚙️ Developer UtilitiesFree
Capacitor energy calculator
E = ½CV² in joules, free
S
POST /elec/capacitor-energy$0.002⚙️ Developer UtilitiesFree
Speaker crossover calculator
frequency from L and C, free
S
POST /elec/crossover-frequency$0.002⚙️ Developer UtilitiesFree
dBm to dBW calculator
convert dBm to dBW, free
S
POST /elec/dbm-to-dbw$0.002⚙️ Developer UtilitiesFree
dBm to watts calculator
convert dBm to W and mW, free
S
POST /elec/dbm-to-watts$0.002⚙️ Developer UtilitiesFree
Electric potential calculator
V=kQ/r for a point charge, free
S
POST /elec/electric-potential$0.002⚙️ Developer UtilitiesFree
EMF terminal voltage calculator
V = ε − Ir free
S
POST /elec/emf-internal-resistance$0.002⚙️ Developer UtilitiesFree
Inductor energy calculator
E = ½LI² in joules, free
S
POST /elec/inductor-energy$0.002⚙️ Developer UtilitiesFree
kWh calculator
energy from watts and running time, free
S
POST /elec/kwh-calculator$0.002⚙️ Developer UtilitiesFree
Inverting amplifier calculator
op-amp gain Av = −Rf/Rin, free
S
POST /elec/op-amp-inverting$0.002⚙️ Developer UtilitiesFree
Electrical power calculator
P=VI and P=I²R from any two values, free
S
POST /elec/power-vi$0.002⚙️ Developer UtilitiesFree
Parallel resistance calculator
equivalent Req from R1∥R2∥…, free
S
POST /elec/resistors-parallel$0.002⚙️ Developer UtilitiesFree
RLC resonant frequency calculator
f₀ and Q from L, C, R, free
S
POST /elec/rlc-resonance$0.002⚙️ Developer UtilitiesFree
Smoothing capacitor calculator
C = I/(2f·Vr) filter size, free
S
POST /elec/smoothing-capacitor$0.002⚙️ Developer UtilitiesFree
Solenoid magnetic field calculator
B = μ₀ n I, free
S
POST /elec/solenoid-field$0.002⚙️ Developer UtilitiesFree
Baconian cipher encoder and decoder
five-letter A/B codes, free
S
POST /enc/bacon$0.002⚙️ Developer UtilitiesFree
Base45 encoder and decoder
RFC 9285 for QR credentials, free
S
POST /enc/base45$0.002⚙️ Developer UtilitiesFree
Base64url encoder and decoder
URL-safe, no padding, free
S
POST /enc/base64url$0.002⚙️ Developer UtilitiesFree
Columnar transposition cipher
encrypt decrypt with keyword, free
S
POST /enc/columnar$0.002⚙️ Developer UtilitiesFree
Text to ASCII codes converter
decimal char codes, free
S
POST /enc/decimal-ascii$0.002⚙️ Developer UtilitiesFree
Four-square cipher encoder and decoder
two keywords, free
S
POST /enc/four-square$0.002⚙️ Developer UtilitiesFree
HTML entities encoder and decoder
named and numeric, free
S
POST /enc/html-entities$0.002⚙️ Developer UtilitiesFree
Morse code translator
encode and decode text free
S
POST /enc/morse$0.002⚙️ Developer UtilitiesFree
Quoted-printable encoder and decoder
MIME QP encode/decode, free
S
POST /enc/quoted-printable$0.002⚙️ Developer UtilitiesFree
ROT47 encoder and decoder
printable ASCII cipher, free
S
POST /enc/rot47$0.002⚙️ Developer UtilitiesFree
Flag semaphore translator
encode and decode arm positions free
S
POST /enc/semaphore$0.002⚙️ Developer UtilitiesFree
Trithemius cipher encoder and decoder
progressive shift, free
S
POST /enc/trithemius$0.002⚙️ Developer UtilitiesFree
Vigenère cipher encoder and decoder
keyword polyalphabetic, free
S
POST /enc/vigenere$0.002⚙️ Developer UtilitiesFree
Base36 encoder
convert integer to or from base-36 (0-9 A-Z), free
S
POST /fmt/base36$0.002⚙️ Developer UtilitiesFree
BCD converter
decimal ↔ 8421 binary-coded decimal, free
S
POST /fmt/bcd$0.002⚙️ Developer UtilitiesFree
Binary to decimal converter
base-2 to base-10, free
S
POST /fmt/binary-decimal$0.002⚙️ Developer UtilitiesFree
Decimal to hex converter
base-10 integer to base-16, free
S
POST /fmt/decimal-hex$0.002⚙️ Developer UtilitiesFree
Engineering notation converter
SI prefixes, free
S
POST /fmt/engineering-notation$0.002⚙️ Developer UtilitiesFree
Greek numeral converter
Ionic numerals with keraia, free
S
POST /fmt/greek-numerals$0.002⚙️ Developer UtilitiesFree
Percent to fraction converter
reduced fraction from %, free
S
POST /fmt/percent-fraction$0.002⚙️ Developer UtilitiesFree
Roman fraction converter
uncia notation from twelfths, free
S
POST /fmt/roman-fraction$0.002⚙️ Developer UtilitiesFree
Significant figures rounder
round to N sig figs, free
S
POST /fmt/sig-figs$0.002⚙️ Developer UtilitiesFree
Along-track distance calculator
great-circle projection, free
S
POST /geo/along-track-distance$0.002⚙️ Developer UtilitiesFree
Compass direction to bearing
32-point name to degrees, free
S
POST /geo/compass-to-bearing$0.002⚙️ Developer UtilitiesFree
Geohash decoder
latitude, longitude & cell error, free
S
POST /geo/geohash-decode$0.002⚙️ Developer UtilitiesFree
Great-circle path intersection
two bearings meet, free
S
POST /geo/great-circle-intersection$0.002⚙️ Developer UtilitiesFree
Magnetic to true bearing
declination conversion both ways, free
S
POST /geo/magnetic-true-bearing$0.002⚙️ Developer UtilitiesFree
Geographic polygon area
spherical m² from lat/lon ring, free
S
POST /geo/polygon-area$0.002⚙️ Developer UtilitiesFree
Rhumb line distance calculator
constant-bearing path, free
S
POST /geo/rhumb-distance$0.002⚙️ Developer UtilitiesFree
Map tile to lat/lon
slippy XYZ north-west corner, free
S
POST /geo/tile-to-latlon$0.002⚙️ Developer UtilitiesFree
UTM to lat/lon converter
zone, easting, northing to WGS84, free
S
POST /geo/utm-to-latlon$0.002⚙️ Developer UtilitiesFree
Web Mercator projection calculator
lat/lon to EPSG:3857 X/Y meters, free
S
POST /geo/web-mercator-project$0.002⚙️ Developer UtilitiesFree
Chord length calculator
from radius and angle or distance to center
S
POST /geom/chord-length$0.002⚙️ Developer UtilitiesFree
Circle through three points
find center and radius from three coordinates
S
POST /geom/circle-from-3-points$0.002⚙️ Developer UtilitiesFree
Cone volume calculator
volume, slant height, lateral and total surface
S
POST /geom/cone$0.002⚙️ Developer UtilitiesFree
Dodecahedron calculator
volume and surface area from edge length
S
POST /geom/dodecahedron$0.002⚙️ Developer UtilitiesFree
Ellipse calculator
area, Ramanujan perimeter, eccentricity, foci
S
POST /geom/ellipse$0.002⚙️ Developer UtilitiesFree
Line intersection calculator
two lines in slope-intercept or standard
S
POST /geom/line-intersection$0.002⚙️ Developer UtilitiesFree
Pipe volume calculator
internal and material volume from inner and outer
S
POST /geom/pipe-volume$0.002⚙️ Developer UtilitiesFree
Polygon area calculator
shoelace formula from ordered vertices
S
POST /geom/polygon-area-shoelace$0.002⚙️ Developer UtilitiesFree
Prism surface area calculator
lateral and total area from perimeter
S
POST /geom/prism-surface$0.002⚙️ Developer UtilitiesFree
Pyramid volume calculator
volume, slant height and surface area
S
POST /geom/pyramid$0.002⚙️ Developer UtilitiesFree
Rhombus calculator
area, perimeter, and side from diagonals or angle
S
POST /geom/rhombus$0.002⚙️ Developer UtilitiesFree
Slope calculator
line slope and inclination angle from two points
S
POST /geom/slope$0.002⚙️ Developer UtilitiesFree
Spherical segment calculator
volume and lateral zone area from radius
S
POST /geom/spherical-segment$0.002⚙️ Developer UtilitiesFree
Square pyramid volume
slant height, lateral and total surface area
S
POST /geom/square-pyramid-solver$0.002⚙️ Developer UtilitiesFree
Torus volume calculator
volume and surface area from tube and center
S
POST /geom/torus$0.002⚙️ Developer UtilitiesFree
45-45-90 triangle calculator
legs, hypotenuse, and area from one side
S
POST /geom/triangle-45-45-90$0.002⚙️ Developer UtilitiesFree
Circumcenter calculator
center and radius of a triangle's circumcircle
S
POST /geom/triangle-circumcenter$0.002⚙️ Developer UtilitiesFree
SSA triangle calculator
ambiguous case, zero one or two solutions
S
POST /geom/triangle-ssa$0.002⚙️ Developer UtilitiesFree
Calorie deficit calculator
daily intake from weight-loss goal, free
S
POST /health/calorie-deficit$0.002⚙️ Developer UtilitiesFree
Cycling speed from power calculator
watts, weight, grade & CdA, free
S
POST /health/cycling-speed-power$0.002⚙️ Developer UtilitiesFree
Body frame size calculator
small, medium or large from height &, free
S
POST /health/frame-size$0.002⚙️ Developer UtilitiesFree
Lean body mass calculator
Boer formula from weight, height & sex, free
S
POST /health/lean-body-mass$0.002⚙️ Developer UtilitiesFree
Maximum heart rate calculator
Fox, Tanaka, Gulati formulas free
S
POST /health/max-heart-rate$0.002⚙️ Developer UtilitiesFree
Pace to speed converter
min/km or min/mi to km/h and mph, free
S
POST /health/pace-to-speed$0.002⚙️ Developer UtilitiesFree
Pulse pressure calculator
systolic minus diastolic, free
S
POST /health/pulse-pressure$0.002⚙️ Developer UtilitiesFree
Swimming calorie calculator
calories burned by duration, weight
S
POST /health/swimming-calories$0.002⚙️ Developer UtilitiesFree
Rockport one-mile walk VO2 max calculator
free estimate
S
POST /health/vo2max-rockport$0.002⚙️ Developer UtilitiesFree
Walking calorie calculator
calories burned from distance, pace, weight
S
POST /health/walking-calories$0.002⚙️ Developer UtilitiesFree
Guitar capo key calculator
sounding key and chords from shapes and fret
S
POST /hobby/capo-key$0.002⚙️ Developer UtilitiesFree
Crochet yarn estimator
length from dimensions, gauge and yardage
S
POST /hobby/crochet-yarn$0.002⚙️ Developer UtilitiesFree
Dice probability calculator
exact P(sum) for n dice, free
S
POST /hobby/dice-probability$0.002⚙️ Developer UtilitiesFree
Flash guide number calculator
aperture or distance from GN and ISO
S
POST /hobby/flash-guide-number$0.002⚙️ Developer UtilitiesFree
Frequency to note calculator
nearest note, octave and cents from Hz
S
POST /hobby/frequency-to-note$0.002⚙️ Developer UtilitiesFree
Hyperfocal distance calculator
H and near limit from f, N, CoC
S
POST /hobby/hyperfocal$0.002⚙️ Developer UtilitiesFree
Line height calculator
px from font size and ratio, free
S
POST /hobby/line-height$0.002⚙️ Developer UtilitiesFree
500 rule calculator
max shutter before star trails (focal × crop)
S
POST /hobby/rule-500$0.002⚙️ Developer UtilitiesFree
Baseboard trim calculator
pieces from room perimeter and door, free
S
POST /home/baseboard$0.002⚙️ Developer UtilitiesFree
Brick calculator
bricks needed from wall area, free
S
POST /home/bricks$0.002⚙️ Developer UtilitiesFree
Drywall sheet calculator
sheets and screws from wall and ceiling, free
S
POST /home/drywall$0.002⚙️ Developer UtilitiesFree
Fence picket calculator
pickets from length, width and gap, free
S
POST /home/fence-pickets$0.002⚙️ Developer UtilitiesFree
Grass seed calculator
seed amount from lawn area and rate, free
S
POST /home/grass-seed$0.002⚙️ Developer UtilitiesFree
Mulch calculator
cubic yards and bags from bed area and depth, free
S
POST /home/mulch$0.002⚙️ Developer UtilitiesFree
Paint quantity calculator
liters from wall area or room size, free
S
POST /home/paint-needed$0.002⚙️ Developer UtilitiesFree
Rafter length calculator
common rafter from span, free
S
POST /home/rafter-length$0.002⚙️ Developer UtilitiesFree
Retaining wall block calculator
blocks and courses from length, free
S
POST /home/retaining-wall-blocks$0.002⚙️ Developer UtilitiesFree
Tile grout calculator
kg from tile size, joint width and area, free
S
POST /home/tile-grout$0.002⚙️ Developer UtilitiesFree
Room wall area calculator
net paintable walls from L×W×H, free
S
POST /home/wall-area$0.002⚙️ Developer UtilitiesFree
Cost per day calculator
annual price to daily, weekly, monthly, free
S
POST /life/cost-per-day$0.002⚙️ Developer UtilitiesFree
Cost per use calculator
price divided by expected uses, free
S
POST /life/cost-per-use$0.002⚙️ Developer UtilitiesFree
Emergency fund calculator
months of essential expenses, free
S
POST /life/emergency-fund$0.002⚙️ Developer UtilitiesFree
Hourly to salary converter
annual pay from wage, hours, weeks free
S
POST /life/hourly-to-salary$0.002⚙️ Developer UtilitiesFree
Reverse sales tax calculator
pre-tax price from tax-inclusive total, free
S
POST /life/reverse-sales-tax$0.002⚙️ Developer UtilitiesFree
Rule of 72 calculator
years to double at a growth rate, free
S
POST /life/rule-of-72$0.002⚙️ Developer UtilitiesFree
Geometric sequence calculator
n-th term and finite sum, free
S
POST /math/geometric-sequence$0.002⚙️ Developer UtilitiesFree
Pell number calculator
P_n = 2P_{n-1}+P_{n-2}, free bigint
S
POST /math/pell-number$0.002⚙️ Developer UtilitiesFree
Perfect square checker
n-th square and isqrt test, free
S
POST /math/square-number$0.002⚙️ Developer UtilitiesFree
Sum of first n cubes
1³+…+n³ = (n(n+1)/2)², free
S
POST /math/sum-of-cubes$0.002⚙️ Developer UtilitiesFree
Superfactorial calculator
product of first n factorials, free bigint
S
POST /math/superfactorial$0.002⚙️ Developer UtilitiesFree
Telescoping series sum
Σ 1/(k(k+1)) = n/(n+1), free
S
POST /math/telescoping-sum$0.002⚙️ Developer UtilitiesFree
Tetrahedral number calculator
n-th Te_n = n(n+1)(n+2)/6, free
S
POST /math/tetrahedral-number$0.002⚙️ Developer UtilitiesFree
Acceleration calculator
a = Δv/t average acceleration, free
S
POST /mech/acceleration$0.002⚙️ Developer UtilitiesFree
Circular motion velocity calculator
v = 2πr/T tangential speed, free
S
POST /mech/circular-velocity$0.002⚙️ Developer UtilitiesFree
Free fall time calculator
t = √(2d/g) from rest, free
S
POST /mech/free-fall-time$0.002⚙️ Developer UtilitiesFree
Friction force calculator
F = μ·N from coefficient and normal force, free
S
POST /mech/friction-force$0.002⚙️ Developer UtilitiesFree
Inelastic collision calculator
common final velocity v_f, free
S
POST /mech/inelastic-collision$0.002⚙️ Developer UtilitiesFree
Lever calculator
effort force for a balanced lever, free
S
POST /mech/lever$0.002⚙️ Developer UtilitiesFree
Gravitational potential energy calculator
PE = m·g·h in joules, free
S
POST /mech/potential-energy$0.002⚙️ Developer UtilitiesFree
Projectile max height calculator
H = v₀² sin²θ / (2g), free
S
POST /mech/projectile-max-height$0.002⚙️ Developer UtilitiesFree
RPM to linear speed calculator
v = 2πr·(rpm/60) rim speed, free
S
POST /mech/rpm-to-linear$0.002⚙️ Developer UtilitiesFree
Spring potential energy calculator
PE = ½kx² in joules, free
S
POST /mech/spring-potential-energy$0.002⚙️ Developer UtilitiesFree
Velocity components calculator
horizontal vx and vertical vy, free
S
POST /mech/velocity-components$0.002⚙️ Developer UtilitiesFree
Weight calculator
W = m·g force in newtons, free
S
POST /mech/weight-force$0.002⚙️ Developer UtilitiesFree
Abundant number checker
aliquot sum and abundance amount, free
S
POST /numth/abundant-number$0.002⚙️ Developer UtilitiesFree
Carmichael function calculator
compute λ(n) for any positive integer
S
POST /numth/carmichael-function$0.002⚙️ Developer UtilitiesFree
Chinese remainder theorem solver
solve x ≡ ai mod ni, free
S
POST /numth/chinese-remainder$0.002⚙️ Developer UtilitiesFree
Collatz conjecture calculator
3n+1 sequence, steps and peak, free
S
POST /numth/collatz$0.002⚙️ Developer UtilitiesFree
Coprime checker
test gcd(a,b)=1 and return the gcd, free
S
POST /numth/coprime-checker$0.002⚙️ Developer UtilitiesFree
Kaprekar number checker
square splits that add back to n, free
S
POST /numth/kaprekar-number$0.002⚙️ Developer UtilitiesFree
Nth prime calculator
find the n-th prime number, free
S
POST /numth/nth-prime$0.002⚙️ Developer UtilitiesFree
Prime factorization calculator
factor any integer into prime powers
S
POST /numth/prime-factorization$0.002⚙️ Developer UtilitiesFree
Primitive root calculator
smallest generator mod prime p, free
S
POST /numth/primitive-root$0.002⚙️ Developer UtilitiesFree
Smith number checker
digit sum vs prime-factor digit sum, free
S
POST /numth/smith-number$0.002⚙️ Developer UtilitiesFree
Double slit calculator
fringe spacing Δy = λL/d, free
S
POST /optics/double-slit$0.002⚙️ Developer UtilitiesFree
Focal length calculator
lens f from object & image distance, free
S
POST /optics/focal-length$0.002⚙️ Developer UtilitiesFree
Refractive index calculator
n = c/v or speed from n, free
S
POST /optics/refractive-index$0.002⚙️ Developer UtilitiesFree
Thin lens calculator
image distance & magnification, free
S
POST /optics/thin-lens$0.002⚙️ Developer UtilitiesFree
Sound level distance calculator
inverse-square dB from one range, free
S
POST /phys/decibel-distance$0.002⚙️ Developer UtilitiesFree
Frequency calculator
f = v / λ from wave speed and wavelength, free
S
POST /phys/frequency$0.002⚙️ Developer UtilitiesFree
String harmonic frequency calculator
f₁ = (1/2L)√(T/μ), free
S
POST /phys/harmonic-string$0.002⚙️ Developer UtilitiesFree
Bayes theorem calculator
posterior from prior, sensitivity, FPR, free
S
POST /prob/bayes-theorem$0.002⚙️ Developer UtilitiesFree
Binomial probability calculator
P(X=k), CDF, mean, variance, free
S
POST /prob/binomial-distribution$0.002⚙️ Developer UtilitiesFree
Lottery odds calculator
match m of r in n-choose-r, optional bonus, free
S
POST /prob/lottery-odds$0.002⚙️ Developer UtilitiesFree
Negative binomial calculator
P(r-th success on trial k), free
S
POST /prob/negative-binomial$0.002⚙️ Developer UtilitiesFree
Factor of safety calculator
n = ultimate strength / working stress, free
S
POST /sci/factor-of-safety$0.002⚙️ Developer UtilitiesFree
Poisson's ratio calculator
ν = −ε_lateral/ε_axial from strains, free
S
POST /sci/poisson-ratio$0.002⚙️ Developer UtilitiesFree
Engineering strain calculator
ε = ΔL/L₀ as ratio and percent, free
S
POST /sci/strain$0.002⚙️ Developer UtilitiesFree
Correlation coefficient calculator
Pearson r for two series, free
S
POST /stat/correlation$0.002⚙️ Developer UtilitiesFree
Mean absolute deviation calculator
MAD about the mean, free
S
POST /stat/mean-absolute-deviation$0.002⚙️ Developer UtilitiesFree
Percentile calculator
k-th percentile & rank by linear, free
S
POST /stat/percentile$0.002⚙️ Developer UtilitiesFree
Standard deviation calculator
population & sample σ, variance, free
S
POST /stat/standard-deviation$0.002⚙️ Developer UtilitiesFree
Convert to alternating case
aLtErNaTiNg text converter, free
S
POST /str/alternating-case$0.002⚙️ Developer UtilitiesFree
Convert to camelCase
phrase to camelCase converter, free
S
POST /str/camel-case$0.002⚙️ Developer UtilitiesFree
Count characters
with/without spaces and UTF-8 bytes, free
S
POST /str/char-count$0.002⚙️ Developer UtilitiesFree
Convert to CONSTANT_CASE
phrase to SCREAMING_SNAKE_CASE, free
S
POST /str/constant-case$0.002⚙️ Developer UtilitiesFree
Count vowels and consonants
digits and other chars too, free
S
POST /str/count-vowels$0.002⚙️ Developer UtilitiesFree
Word frequency counter
count and rank words in text, free
S
POST /str/frequency$0.002⚙️ Developer UtilitiesFree
Remove all whitespace
strip spaces, tabs, line breaks free
S
POST /str/remove-whitespace$0.002⚙️ Developer UtilitiesFree
Repeat text
string repeater with optional separator, free
S
POST /str/repeat$0.002⚙️ Developer UtilitiesFree
Text to slug
URL-friendly titles with hyphens, free
S
POST /str/slugify$0.002⚙️ Developer UtilitiesFree
Convert to uppercase
all-caps text converter, free
S
POST /str/uppercase$0.002⚙️ Developer UtilitiesFree
Boiling point altitude calculator
water Tb vs elevation or pressure, free
S
POST /thermo/boiling-point-altitude$0.002⚙️ Developer UtilitiesFree
Combined gas law calculator
P₁V₁/T₁ = P₂V₂/T₂, free
S
POST /thermo/combined-gas-law$0.002⚙️ Developer UtilitiesFree
Coefficient of performance calculator
COP = Q/W refrigerator &, free
S
POST /thermo/cop-refrigerator$0.002⚙️ Developer UtilitiesFree
Volumetric flow rate calculator
Q = A·v pipe discharge, free
S
POST /thermo/flow-rate$0.002⚙️ Developer UtilitiesFree
Carnot efficiency calculator
η = 1 − Tc/Th heat engine limit, free
S
POST /thermo/heat-engine-efficiency$0.002⚙️ Developer UtilitiesFree
Latent heat calculator
Q = mL phase-change energy, free
S
POST /thermo/latent-heat$0.002⚙️ Developer UtilitiesFree
Poiseuille flow calculator
Q = π r⁴ ΔP / (8 μ L), free
S
POST /thermo/poiseuille-flow$0.002⚙️ Developer UtilitiesFree
Stefan-Boltzmann calculator
P = εσAT⁴ radiated power, free
S
POST /thermo/stefan-boltzmann$0.002⚙️ Developer UtilitiesFree
Volumetric expansion calculator
ΔV = V₀βΔT thermal volume change, free
S
POST /thermo/volumetric-expansion$0.002⚙️ Developer UtilitiesFree
Carry-on size checker
does your bag fit airline limits, free
S
POST /travel/carry-on-check$0.002⚙️ Developer UtilitiesFree
EV range calculator
km or miles from battery kWh and efficiency, free
S
POST /travel/ev-range$0.002⚙️ Developer UtilitiesFree
Jet lag recovery calculator
days to adjust by time zones, free
S
POST /travel/jet-lag-recovery$0.002⚙️ Developer UtilitiesFree
Layover connection time checker
length vs minimum MCT, free
S
POST /travel/layover-time$0.002⚙️ Developer UtilitiesFree
Trip fuel volume calculator
liters or gallons from distance and MPG, free
S
POST /travel/trip-fuel-volume$0.002⚙️ Developer UtilitiesFree
Trip total cost calculator
fuel, tolls, lodging and food budget, free
S
POST /travel/trip-total-cost$0.002⚙️ Developer UtilitiesFree
Degrees to radians converter
and back, free online
S
POST /trig/deg-to-rad$0.002⚙️ Developer UtilitiesFree
Hypotenuse calculator
find c or a missing leg free online
S
POST /trig/hypotenuse$0.002⚙️ Developer UtilitiesFree
Arcsine calculator
asin in degrees and radians, free
S
POST /trig/inverse-sin$0.002⚙️ Developer UtilitiesFree
Trig identity verifier
Pythagorean and quotient residuals, free
S
POST /trig/pythagorean-identity$0.002⚙️ Developer UtilitiesFree
Secant, cosecant & cotangent calculator
free online
S
POST /trig/secant-cosecant$0.002⚙️ Developer UtilitiesFree
Unit circle calculator
cos, sin, and radians, free online
S
POST /trig/unit-circle$0.002⚙️ Developer UtilitiesFree
Binomial expansion calculator
expand (a+b)^n, free
A
POST /algebra/binomial-expansion$0.002⚙️ Developer UtilitiesFree
Cramer's rule calculator
solve Ax=b with determinants, free
A
POST /algebra/cramers-rule$0.002⚙️ Developer UtilitiesFree
Cubic equation solver
all three roots of ax³+bx²+cx+d=0 via Cardano, free
A
POST /algebra/cubic-equation$0.002⚙️ Developer UtilitiesFree
Discriminant calculator
b² − 4ac and root type, free
P
POST /algebra/discriminant$0.002⚙️ Developer UtilitiesFree
Dot product calculator
vectors, angle, free online
P
POST /algebra/dot-product$0.002⚙️ Developer UtilitiesFree
2×2 eigenvalue calculator
characteristic equation, free
P
POST /algebra/eigenvalues-2x2$0.002⚙️ Developer UtilitiesFree
Exponential equation solver
solve b^x = y for x with logs, free
A
POST /algebra/exponential-equation$0.002⚙️ Developer UtilitiesFree
Factor quadratic calculator
ax²+bx+c into binomials over rationals, free
A
POST /algebra/factor-quadratic$0.002⚙️ Developer UtilitiesFree
Gaussian elimination solver
solve Ax = b with back-substitution, free
A
POST /algebra/gaussian-elimination$0.002⚙️ Developer UtilitiesFree
Linear equation solver
solve ax + b = c for x, free
P
POST /algebra/linear-equation$0.002⚙️ Developer UtilitiesFree
Logarithm expand & condense
product, quotient, power laws, free
P
POST /algebra/log-expand$0.002⚙️ Developer UtilitiesFree
Logarithm calculator
log base b of x, ln and log10, free
A
POST /algebra/logarithm$0.002⚙️ Developer UtilitiesFree
Matrix addition & subtraction
entrywise, free online
A
POST /algebra/matrix-add$0.002⚙️ Developer UtilitiesFree
Matrix determinant calculator
det(A) via cofactor expansion or LU, free
A
POST /algebra/matrix-determinant$0.002⚙️ Developer UtilitiesFree
Matrix rank calculator
row echelon form and pivots, free
P
POST /algebra/matrix-rank$0.002⚙️ Developer UtilitiesFree
Matrix trace calculator
sum of main diagonal entries of a square matrix, free
A
POST /algebra/matrix-trace$0.002⚙️ Developer UtilitiesFree
Matrix transpose calculator
swap rows and columns, free online
A
POST /algebra/matrix-transpose$0.002⚙️ Developer UtilitiesFree
Partial fraction decomposition
proper rational with linear & quadratic factors, free
A
POST /algebra/partial-fractions$0.002⚙️ Developer UtilitiesFree
Polynomial addition calculator
add or subtract coefficient lists, simplified result, free
A
POST /algebra/polynomial-add$0.002⚙️ Developer UtilitiesFree
Polynomial multiplication calculator
multiply two coefficient lists, free
P
POST /algebra/polynomial-multiply$0.002⚙️ Developer UtilitiesFree
Polynomial root finder
all real roots from coefficients, free
A
POST /algebra/polynomial-roots$0.002⚙️ Developer UtilitiesFree
Quadratic formula solver
roots, discriminant and vertex of ax²+bx+c=0, free
A
POST /algebra/quadratic-formula$0.002⚙️ Developer UtilitiesFree
Rational root theorem
list candidate roots p/q, free
A
POST /algebra/rational-root$0.002⚙️ Developer UtilitiesFree
Remainder theorem calculator
evaluate p(r) by Horner, free
P
POST /algebra/remainder-theorem$0.002⚙️ Developer UtilitiesFree
Synthetic division calculator
divide by x − r, free
A
POST /algebra/synthetic-division$0.002⚙️ Developer UtilitiesFree
Solve a 2×2 system of linear equations
Cramer's rule, free
A
POST /algebra/system-2x2$0.002⚙️ Developer UtilitiesFree
Vector magnitude calculator
Euclidean norm and unit vector, free
A
POST /algebra/vector-magnitude$0.002⚙️ Developer UtilitiesFree
Vector projection calculator
scalar & vector proj, free
A
POST /algebra/vector-projection$0.002⚙️ Developer UtilitiesFree
Vieta's formulas calculator
sum and product of polynomial roots from coefficients, free
A
POST /algebra/vieta-formulas$0.002⚙️ Developer UtilitiesFree
Angular size calculator
diameter in degrees & arcmin, free
P
POST /astro/angular-size$0.002⚙️ Developer UtilitiesFree
Apoapsis and periapsis calculator
from semi-major axis and eccentricity, free
A
POST /astro/apoapsis-periapsis$0.002⚙️ Developer UtilitiesFree
Apparent brightness calculator
L/(4πd²) inverse square, free
P
POST /astro/apparent-brightness$0.002⚙️ Developer UtilitiesFree
Planet escape velocity calculator
v = √(2GM/r), free
P
POST /astro/body-escape-velocity$0.002⚙️ Developer UtilitiesFree
Distance modulus calculator
parsecs & light-years, free
A
POST /astro/distance-modulus$0.002⚙️ Developer UtilitiesFree
Geostationary orbit calculator
altitude from mass and rotation period, free
A
POST /astro/geostationary-orbit$0.002⚙️ Developer UtilitiesFree
Gravitational force calculator
Newton's law F=Gm₁m₂/r² free
A
POST /astro/gravitational-force$0.002⚙️ Developer UtilitiesFree
Hubble law calculator
galaxy distance from recession velocity and H0, free
A
POST /astro/hubble-distance$0.002⚙️ Developer UtilitiesFree
Light-year converter
km, parsecs and AU, free
A
POST /astro/light-year-distance$0.002⚙️ Developer UtilitiesFree
Orbital energy calculator
potential and total energy from mass and radius, free
A
POST /astro/orbital-energy$0.002⚙️ Developer UtilitiesFree
Orbital period calculator
Kepler T from semi-major axis and mass, free
A
POST /astro/orbital-period$0.002⚙️ Developer UtilitiesFree
Orbital velocity calculator
circular speed from mass and radius, free
A
POST /astro/orbital-velocity$0.002⚙️ Developer UtilitiesFree
Stellar parallax calculator
star distance from parallax angle in parsecs and light-years, free
A
POST /astro/parallax-distance$0.002⚙️ Developer UtilitiesFree
Redshift calculator
z and recession velocity from wavelengths, free
P
POST /astro/redshift-velocity$0.002⚙️ Developer UtilitiesFree
Roche limit calculator
tidal breakup distance from densities and radius, free
A
POST /astro/roche-limit$0.002⚙️ Developer UtilitiesFree
Synodic period calculator
from two orbital periods, free
A
POST /astro/synodic-period$0.002⚙️ Developer UtilitiesFree
Rocket equation calculator
Δv = ve·ln(m₀/m_f), free
P
POST /astro/tsiolkovsky-rocket$0.002⚙️ Developer UtilitiesFree
Weight on other planets calculator
Earth weight to Mercury Mars Jupiter free
A
POST /astro/weight-on-planet$0.002⚙️ Developer UtilitiesFree
Actual yield calculator
from theoretical yield and percent yield, free
A
POST /chem/actual-yield-from-percent$0.002⚙️ Developer UtilitiesFree
Activation energy calculator
Ea from two rate constants, free
P
POST /chem/arrhenius-activation-energy$0.002⚙️ Developer UtilitiesFree
Arrhenius pre-exponential factor calculator
A from k, Ea, T, free
A
POST /chem/arrhenius-prefactor$0.002⚙️ Developer UtilitiesFree
Atom economy calculator
green chemistry AE free
A
POST /chem/atom-economy$0.002⚙️ Developer UtilitiesFree
Atoms to moles of compound calculator
n = N/(k·N_A), free
P
POST /chem/atoms-to-moles-of-compound$0.002⚙️ Developer UtilitiesFree
Average atomic mass calculator
from isotope masses and abundances
A
POST /chem/average-atomic-mass$0.002⚙️ Developer UtilitiesFree
Average kinetic energy of gas calculator
(3/2)kT per molecule, free
A
POST /chem/average-kinetic-energy-gas$0.002⚙️ Developer UtilitiesFree
Avogadro's law calculator
final gas volume from moles, free
P
POST /chem/avogadro-law$0.002⚙️ Developer UtilitiesFree
Moles to atoms calculator
Avogadro's number N = n·N_A, free
P
POST /chem/avogadro-number$0.002⚙️ Developer UtilitiesFree
Bomb calorimeter calculator
molar heat of combustion from C, ΔT, n
A
POST /chem/bomb-calorimetry$0.002⚙️ Developer UtilitiesFree
Bond energy reaction enthalpy calculator
ΔH from bonds
A
POST /chem/bond-enthalpy-reaction$0.002⚙️ Developer UtilitiesFree
Boyle's law calculator
final gas pressure from volume, free
P
POST /chem/boyle-final-pressure$0.002⚙️ Developer UtilitiesFree
Boyle's law final volume calculator
V2 from P1, V1, P2 at constant T, free
A
POST /chem/boyle-final-volume$0.002⚙️ Developer UtilitiesFree
Buffer capacity calculator
β from acid and conjugate base, free
P
POST /chem/buffer-capacity$0.002⚙️ Developer UtilitiesFree
Buffer pOH calculator
pOH from pKb and concentrations, free
A
POST /chem/buffer-poh$0.002⚙️ Developer UtilitiesFree
C1V1 = C2V2 calculator
solve dilution for concentration or volume, free
P
POST /chem/c1v1-c2v2$0.002⚙️ Developer UtilitiesFree
Calorimeter constant calculator
C = q/ΔT from heat and temperature change
P
POST /chem/calorimeter-constant$0.002⚙️ Developer UtilitiesFree
Calorimetry heat released calculator
Q = m·c·ΔT from mass, specific heat and ΔT, free
A
POST /chem/calorimetry-heat$0.002⚙️ Developer UtilitiesFree
Catalyst rate enhancement calculator
k_cat/k_uncat from Ea, free
A
POST /chem/catalyst-rate-enhancement$0.002⚙️ Developer UtilitiesFree
Cell potential from Gibbs free energy
E° = −ΔG°/(nF)
P
POST /chem/cell-potential-from-gibbs$0.002⚙️ Developer UtilitiesFree
Charles law final temperature calculator
T2 from V1, T1, V2 free
A
POST /chem/charles-final-temperature$0.002⚙️ Developer UtilitiesFree
Clausius–Clapeyron calculator
T2 from two vapor pressures, free
P
POST /chem/clausius-clapeyron$0.002⚙️ Developer UtilitiesFree
Colligative particle concentration calculator
M×i effective particles, free
A
POST /chem/colligative-particle-count$0.002⚙️ Developer UtilitiesFree
Collision theory rate calculator
k = p·Z·e^(−Ea/RT), free
P
POST /chem/collision-frequency-factor$0.002⚙️ Developer UtilitiesFree
Combined equilibrium constant calculator
overall K from steps, free
A
POST /chem/combined-equilibrium-constant$0.002⚙️ Developer UtilitiesFree
Combined gas law final pressure calculator
P2 from V2, T2 free
A
POST /chem/combined-gas-final-pressure$0.002⚙️ Developer UtilitiesFree
Combustion analysis calculator
empirical formula from CO2 and H2O, free
A
POST /chem/combustion-analysis$0.002⚙️ Developer UtilitiesFree
Common ion effect solubility calculator
reduced molar solubility from Ksp, free
P
POST /chem/common-ion-solubility$0.002⚙️ Developer UtilitiesFree
Gas compressibility factor calculator
Z = PVm/RT for real gases, free
A
POST /chem/compressibility-factor$0.002⚙️ Developer UtilitiesFree
Concentration after evaporation calculator
concentrated solution from volume lost, free
P
POST /chem/concentration-after-evaporation$0.002⚙️ Developer UtilitiesFree
Conjugate base to acid ratio calculator
[A−]/[HA] from pH and pKa, free
P
POST /chem/conjugate-ratio$0.002⚙️ Developer UtilitiesFree
Faraday corrosion rate calculator
penetration rate from i_corr, free
P
POST /chem/corrosion-rate-faraday$0.002⚙️ Developer UtilitiesFree
Van der Waals critical constants calculator
Tc, Pc, Vc from a and b, free
A
POST /chem/critical-constants$0.002⚙️ Developer UtilitiesFree
Partial pressures from mole amounts
Dalton Pi=(ni/n)·P, free
A
POST /chem/dalton-from-moles$0.002⚙️ Developer UtilitiesFree
Gas mole fraction from partial pressure
Dalton yi=Pi/P, free
A
POST /chem/dalton-mole-fraction$0.002⚙️ Developer UtilitiesFree
Degree of dissociation calculator
α from C₀ and Ceq, free
A
POST /chem/degree-of-dissociation$0.002⚙️ Developer UtilitiesFree
Density calculator
ρ=m/V from mass and volume, free
A
POST /chem/density-mass-volume$0.002⚙️ Developer UtilitiesFree
Dilution calculator
solve M1V1=M2V2 for concentration or volume
A
POST /chem/dilution$0.002⚙️ Developer UtilitiesFree
Dilution factor calculator
DF and fold dilution from volumes
A
POST /chem/dilution-factor-from-volumes$0.002⚙️ Developer UtilitiesFree
pH after dilution calculator
strong acid pH from volumes, free
P
POST /chem/dilution-ph-strong-acid$0.002⚙️ Developer UtilitiesFree
Dilution to target ppm calculator
stock volume for a final ppm
A
POST /chem/dilution-to-target-ppm$0.002⚙️ Developer UtilitiesFree
Dilution water to add calculator
volume from C1 V1 C2 free
A
POST /chem/dilution-water-added$0.002⚙️ Developer UtilitiesFree
Ebullioscopic constant calculator
Kb from ΔTb, molality and van't Hoff factor
P
POST /chem/ebullioscopic-constant$0.002⚙️ Developer UtilitiesFree
Electrode potential vs pH calculator
hydrogen electrode Nernst, free
P
POST /chem/electrode-potential-ph$0.002⚙️ Developer UtilitiesFree
Electrolysis time calculator
time to deposit mass from I, m, M, n, free
A
POST /chem/electrolysis-time$0.002⚙️ Developer UtilitiesFree
Electron configuration calculator
ground-state config and valence electrons from atomic number, free
A
POST /chem/electron-configuration$0.002⚙️ Developer UtilitiesFree
Electrorefining efficiency calculator
current efficiency from actual vs theoretical mass, free
A
POST /chem/electrorefining-efficiency$0.002⚙️ Developer UtilitiesFree
Empirical formula calculator
from mass or percent composition
A
POST /chem/empirical-formula$0.002⚙️ Developer UtilitiesFree
Empirical formula from masses calculator
ratio from mass and atomic mass
A
POST /chem/empirical-from-masses$0.002⚙️ Developer UtilitiesFree
Reaction heat for amount calculator
Q = n·ΔH from moles and molar enthalpy, free
A
POST /chem/enthalpy-amount-scaling$0.002⚙️ Developer UtilitiesFree
Enthalpy scaled by coefficients calculator
ΔH × factor for thermochemical equations, free
A
POST /chem/enthalpy-coefficient-scaling$0.002⚙️ Developer UtilitiesFree
Heat of combustion per gram calculator
energy from molar ΔH and molar mass
P
POST /chem/enthalpy-combustion-per-gram$0.002⚙️ Developer UtilitiesFree
Enthalpy of dilution calculator
molar ΔH_dil = q/n from heat and moles, free
A
POST /chem/enthalpy-dilution$0.002⚙️ Developer UtilitiesFree
Enthalpy from heats of formation calculator
ΔH°_rxn free
A
POST /chem/enthalpy-from-formation$0.002⚙️ Developer UtilitiesFree
Enthalpy from internal energy calculator
ΔH = ΔU + Δn_g RT
A
POST /chem/enthalpy-from-internal-energy$0.002⚙️ Developer UtilitiesFree
Enthalpy of fusion calculator
ΔH_fus from heat and moles
A
POST /chem/enthalpy-of-fusion-moles$0.002⚙️ Developer UtilitiesFree
Enthalpy of vaporization calculator
molar ΔH_vap = q/n from heat and moles, free
A
POST /chem/enthalpy-of-vaporization-moles$0.002⚙️ Developer UtilitiesFree
Enthalpy of reaction calculator
ΔH from formation enthalpies
A
POST /chem/enthalpy-reaction$0.002⚙️ Developer UtilitiesFree
Reaction entropy change calculator
ΔS from standard molar entropies
A
POST /chem/entropy-of-reaction$0.002⚙️ Developer UtilitiesFree
Equilibrium constant calculator
Kc from concentrations, free
A
POST /chem/equilibrium-constant$0.002⚙️ Developer UtilitiesFree
Equilibrium constant from cell potential
K from E°, n, T, free
A
POST /chem/equilibrium-constant-from-emf$0.002⚙️ Developer UtilitiesFree
Equilibrium partial pressure from Kp calculator
gas stoichiometry, free
P
POST /chem/equilibrium-partial-pressure$0.002⚙️ Developer UtilitiesFree
Equivalent weight calculator
EW = M / n from molar mass and valence, free
P
POST /chem/equivalent-weight$0.002⚙️ Developer UtilitiesFree
Excess reactant remaining calculator
leftover mass free
A
POST /chem/excess-reactant-remaining$0.002⚙️ Developer UtilitiesFree
Faraday electrolysis mass calculator
mass deposited from I, t, M, n, free
A
POST /chem/faraday-mass-deposited$0.002⚙️ Developer UtilitiesFree
Final temperature of mixture calculator
two substances, free
A
POST /chem/final-temperature-two-substances$0.002⚙️ Developer UtilitiesFree
First-order half-life calculator
t½ from rate constant k, free
A
POST /chem/first-order-half-life$0.002⚙️ Developer UtilitiesFree
Formal charge calculator
valence, lone pairs, bonding electrons, free
P
POST /chem/formal-charge$0.002⚙️ Developer UtilitiesFree
Fraction dissociated calculator
α from Ka and concentration, free
P
POST /chem/fraction-dissociated-from-ka$0.002⚙️ Developer UtilitiesFree
Freezing mixture temperature calculator
ice-salt ΔTf from molality, free
A
POST /chem/freezing-mixture-temperature$0.002⚙️ Developer UtilitiesFree
Freezing point depression calculator
ΔTf = i·Kf·m free
A
POST /chem/freezing-point-depression$0.002⚙️ Developer UtilitiesFree
Gas collected over water calculator
dry gas partial pressure free
A
POST /chem/gas-collected-over-water$0.002⚙️ Developer UtilitiesFree
Gas density at STP calculator
ρ from molar mass at 0 °C, 1 atm, free
A
POST /chem/gas-density-at-stp$0.002⚙️ Developer UtilitiesFree
Ideal gas density calculator
ρ=PM/RT from P, M and T, free
A
POST /chem/gas-density-ideal$0.002⚙️ Developer UtilitiesFree
Gas moles calculator
ideal gas n = PV/RT from pressure, volume and temperature, free
A
POST /chem/gas-moles-from-ptv$0.002⚙️ Developer UtilitiesFree
Gas pressure from moles calculator
ideal-gas P=nRT/V, free
A
POST /chem/gas-pressure-from-moles$0.002⚙️ Developer UtilitiesFree
Electrolysis gas volume calculator
Faraday charge to STP volume, free
P
POST /chem/gas-volume-electrolysis$0.002⚙️ Developer UtilitiesFree
Gas volume from moles calculator
V = nRT/P ideal gas, free
P
POST /chem/gas-volume-from-moles$0.002⚙️ Developer UtilitiesFree
Gay-Lussac final pressure calculator
P2 from P1, T1, T2 at constant V, free
A
POST /chem/gay-lussac-final-pressure$0.002⚙️ Developer UtilitiesFree
Gay-Lussac's law calculator
final gas temperature from pressure, free
P
POST /chem/gay-lussac-final-temperature$0.002⚙️ Developer UtilitiesFree
Spontaneity crossover temperature
T where ΔG = 0 from ΔH and ΔS
P
POST /chem/gibbs-crossover-temperature$0.002⚙️ Developer UtilitiesFree
Gibbs free energy calculator
ΔG = ΔH − TΔS from enthalpy, entropy and temperature, free
A
POST /chem/gibbs-free-energy$0.002⚙️ Developer UtilitiesFree
Gibbs energy from equilibrium constant calculator
ΔG° = −RT ln(K), free
A
POST /chem/gibbs-from-equilibrium$0.002⚙️ Developer UtilitiesFree
Non-standard Gibbs free energy calculator
ΔG from ΔG°, Q, T
A
POST /chem/gibbs-non-standard$0.002⚙️ Developer UtilitiesFree
Reaction spontaneity calculator
Gibbs ΔG from ΔH, ΔS, T
A
POST /chem/gibbs-spontaneity$0.002⚙️ Developer UtilitiesFree
Graham's law calculator
effusion rate ratio from molar mass, free
P
POST /chem/graham-effusion-rate-ratio$0.002⚙️ Developer UtilitiesFree
Graham effusion time calculator
t2 from t1 and molar masses, free
A
POST /chem/graham-effusion-time$0.002⚙️ Developer UtilitiesFree
Unknown molar mass from effusion calculator
Graham's law free
A
POST /chem/graham-unknown-molar-mass$0.002⚙️ Developer UtilitiesFree
Grams to moles calculator
n = m/M free
A
POST /chem/grams-to-moles$0.002⚙️ Developer UtilitiesFree
Grams to particles calculator
mass and molar mass to N, free
A
POST /chem/grams-to-particles$0.002⚙️ Developer UtilitiesFree
Half-life calculator
remaining amount after decay, free
A
POST /chem/half-life$0.002⚙️ Developer UtilitiesFree
Number of half-lives calculator
elapsed time over t½, free
A
POST /chem/half-lives-elapsed$0.002⚙️ Developer UtilitiesFree
Molar heat capacity ratio calculator
γ = Cp/Cv, free
P
POST /chem/heat-capacity-ratio$0.002⚙️ Developer UtilitiesFree
Heat of neutralization calculator
molar ΔH from heat and moles of water
P
POST /chem/heat-of-neutralization$0.002⚙️ Developer UtilitiesFree
Heat of solution calculator
molar ΔH_sol = q/n from heat and moles, free
A
POST /chem/heat-of-solution$0.002⚙️ Developer UtilitiesFree
Heat required to raise temperature calculator
Q = m·c·ΔT from mass, c and ΔT, free
A
POST /chem/heat-to-raise-temperature$0.002⚙️ Developer UtilitiesFree
Henderson–Hasselbalch calculator
buffer pH from pKa and ratio, free
P
POST /chem/henderson-hasselbalch$0.002⚙️ Developer UtilitiesFree
Henry's law constant calculator
kH = c/p from concentration and partial pressure
P
POST /chem/henrys-law-constant$0.002⚙️ Developer UtilitiesFree
Henry's law gas solubility calculator
c = k_H · p, free
A
POST /chem/henrys-law-solubility$0.002⚙️ Developer UtilitiesFree
Hess's law calculator
overall reaction enthalpy from steps, free
P
POST /chem/hess-law$0.002⚙️ Developer UtilitiesFree
Hydrate formula calculator
water of crystallization n from mass, free
P
POST /chem/hydrate-formula$0.002⚙️ Developer UtilitiesFree
Hydrogen ion from weak acid calculator
[H+] from C and Ka, free
A
POST /chem/hydrogen-ion-weak-acid$0.002⚙️ Developer UtilitiesFree
Hydroxide concentration from pOH calculator
[OH−] = 10^(−pOH)
A
POST /chem/hydroxide-from-poh$0.002⚙️ Developer UtilitiesFree
Ideal gas law chemistry calculator
solve PV = nRT for P, V, n, or T
P
POST /chem/ideal-gas$0.002⚙️ Developer UtilitiesFree
Integrated rate law order checker
which plot is linear, free
P
POST /chem/integrated-rate-order$0.002⚙️ Developer UtilitiesFree
Internal energy change calculator
ΔU = Q − W first law, free
P
POST /chem/internal-energy-change$0.002⚙️ Developer UtilitiesFree
Ionic strength calculator
I = ½ Σ c_i z_i² free
A
POST /chem/ionic-strength$0.002⚙️ Developer UtilitiesFree
Isotope abundance calculator
percent from average mass, free
A
POST /chem/isotope-abundance$0.002⚙️ Developer UtilitiesFree
Ka from pH calculator
acid dissociation from concentration and pH, free
A
POST /chem/ka-from-ph$0.002⚙️ Developer UtilitiesFree
Kb from pKb calculator
base dissociation constant Kb = 10^(−pKb), free
P
POST /chem/kb-from-pkb$0.002⚙️ Developer UtilitiesFree
Kc from degree of dissociation calculator
equilibrium constant from α and c₀, free
P
POST /chem/kc-from-dissociation$0.002⚙️ Developer UtilitiesFree
Kp from Kc calculator
convert with T and Δn, free
A
POST /chem/kp-kc-conversion$0.002⚙️ Developer UtilitiesFree
Lattice energy calculator
Born–Landé equation, free
A
POST /chem/lattice-energy-born-lande$0.002⚙️ Developer UtilitiesFree
Product mass from limiting reactant calculator
two reagents, free
A
POST /chem/limiting-reactant-product-mass$0.002⚙️ Developer UtilitiesFree
Mass fraction calculator
w and mass % from solute and total mass, free
A
POST /chem/mass-fraction$0.002⚙️ Developer UtilitiesFree
Mass fraction to mole fraction calculator
free
A
POST /chem/mass-fraction-to-mole-fraction$0.002⚙️ Developer UtilitiesFree
Pure mass from purity calculator
impure sample to pure substance mass, free
A
POST /chem/mass-from-purity$0.002⚙️ Developer UtilitiesFree
Mass of element in sample calculator
m_element from sample mass and mass fraction, free
P
POST /chem/mass-of-element-in-sample$0.002⚙️ Developer UtilitiesFree
Mass of product from reactant calculator
grams via mole ratio, free
A
POST /chem/mass-of-product-from-reactant$0.002⚙️ Developer UtilitiesFree
Mass percent calculator
w/w concentration from solute and solution mass, free
P
POST /chem/mass-percent$0.002⚙️ Developer UtilitiesFree
Mass percent to mole fraction calculator
free
A
POST /chem/mass-percent-to-mole-fraction$0.002⚙️ Developer UtilitiesFree
Mass to gas volume stoichiometry calculator
product gas V from mass, free
A
POST /chem/mass-to-volume-gas-stoich$0.002⚙️ Developer UtilitiesFree
Mixing three solutions calculator
final concentration free
A
POST /chem/mixing-three-solutions$0.002⚙️ Developer UtilitiesFree
Mixing two solutions calculator
resulting concentration from C1 V1 + C2 V2
A
POST /chem/mixing-two-solutions$0.002⚙️ Developer UtilitiesFree
Molality calculator
moles of solute per kg of solvent free
A
POST /chem/molality$0.002⚙️ Developer UtilitiesFree
Molality calculator
moles of solute over kg solvent, free
P
POST /chem/molality-from-moles-mass$0.002⚙️ Developer UtilitiesFree
Molality to molarity calculator
convert m to M with density, free
P
POST /chem/molality-to-molarity$0.002⚙️ Developer UtilitiesFree
Molar mass calculator
formula to g/mol from atomic weights
A
POST /chem/molar-mass$0.002⚙️ Developer UtilitiesFree
Molar mass from freezing point depression calculator
free
A
POST /chem/molar-mass-from-fp-depression$0.002⚙️ Developer UtilitiesFree
Molar mass from osmotic pressure
van't Hoff M calculator, free
A
POST /chem/molar-mass-from-osmotic-pressure$0.002⚙️ Developer UtilitiesFree
Molar solubility from Ksp calculator
s from Ksp and stoichiometry, free
A
POST /chem/molar-solubility-from-ksp$0.002⚙️ Developer UtilitiesFree
Molar volume at STP calculator
ideal gas volume from moles at standard T and P, free
A
POST /chem/molar-volume-at-stp$0.002⚙️ Developer UtilitiesFree
Molarity to mass percent calculator
M, density & MM to % w/w
A
POST /chem/molarity-to-mass-percent$0.002⚙️ Developer UtilitiesFree
Molarity to normality calculator
N = M × equivalents per mole
A
POST /chem/molarity-to-normality$0.002⚙️ Developer UtilitiesFree
Mole fraction calculator
x_i from component moles free
A
POST /chem/mole-fraction$0.002⚙️ Developer UtilitiesFree
Mole fraction to molality calculator
convert x to m, free
P
POST /chem/mole-fraction-to-molality$0.002⚙️ Developer UtilitiesFree
Mole fraction to molarity calculator
M from x, ρ free
A
POST /chem/mole-fraction-to-molarity$0.002⚙️ Developer UtilitiesFree
Gas volume ratio calculator
stoichiometric volumes from coefficients, free
P
POST /chem/mole-ratio-gas-volumes$0.002⚙️ Developer UtilitiesFree
Mole to mole conversion calculator
product moles from coefficients free
A
POST /chem/mole-to-mole-conversion$0.002⚙️ Developer UtilitiesFree
Molecular formula calculator
empirical formula to molecular formula from molar mass free
A
POST /chem/molecular-formula$0.002⚙️ Developer UtilitiesFree
Molecular formula from empirical calculator
multiplier n = M / M_emp free
A
POST /chem/molecular-from-empirical$0.002⚙️ Developer UtilitiesFree
Moles to grams calculator
mass ↔ moles via molar mass, free
P
POST /chem/moles-from-mass$0.002⚙️ Developer UtilitiesFree
Moles from molarity and volume calculator
n = M×V free
A
POST /chem/moles-from-molarity-volume$0.002⚙️ Developer UtilitiesFree
Most probable molecular speed calculator
v_mp = √(2RT/M) free
A
POST /chem/most-probable-speed$0.002⚙️ Developer UtilitiesFree
Nernst equation calculator
cell potential from E°, n, Q, free
A
POST /chem/nernst-equation$0.002⚙️ Developer UtilitiesFree
Neutralization moles calculator
excess reagent from C and V
A
POST /chem/neutralization-moles$0.002⚙️ Developer UtilitiesFree
Normality calculator
equivalents per liter of solution free
A
POST /chem/normality$0.002⚙️ Developer UtilitiesFree
Normality to molarity calculator
M = N / n free
A
POST /chem/normality-to-molarity$0.002⚙️ Developer UtilitiesFree
Number of atoms in sample calculator
N = (m/M)·N_A·n free
A
POST /chem/number-of-atoms-in-sample$0.002⚙️ Developer UtilitiesFree
Osmolarity from osmotic pressure calculator
c = π/(RT) free
A
POST /chem/osmolarity-from-osmotic-pressure$0.002⚙️ Developer UtilitiesFree
Osmotic pressure calculator
π = iCRT from concentration, T, and van 't Hoff factor
P
POST /chem/osmotic-pressure$0.002⚙️ Developer UtilitiesFree
Osmotic pressure from molarity calculator
π = iMRT free
A
POST /chem/osmotic-pressure-from-molarity$0.002⚙️ Developer UtilitiesFree
Osmotic pressure difference calculator
Δπ = (c₁−c₂)RT free
A
POST /chem/osmotic-pressure-two-solutions$0.002⚙️ Developer UtilitiesFree
Partial pressure at new temperature calculator
p2 from p1, T1, T2 free
A
POST /chem/partial-pressure-change-temperature$0.002⚙️ Developer UtilitiesFree
Partial pressure from mole fraction calculator
p_i = x_i·P free
A
POST /chem/partial-pressure-from-mole-fraction$0.002⚙️ Developer UtilitiesFree
Particles to grams calculator
mass from count and molar mass, free
P
POST /chem/particles-to-grams$0.002⚙️ Developer UtilitiesFree
Parts per thousand calculator
‰ from solute and total mass, free
A
POST /chem/parts-per-thousand$0.002⚙️ Developer UtilitiesFree
Element percent by mass calculator
% composition from element mass and molar mass, free
P
POST /chem/percent-composition-element$0.002⚙️ Developer UtilitiesFree
Percent dissociation calculator
% at equilibrium from C₀ and Ceq, free
A
POST /chem/percent-dissociation-equilibrium$0.002⚙️ Developer UtilitiesFree
Percent ionization of acid calculator
% from C and Ka, free
A
POST /chem/percent-ionization$0.002⚙️ Developer UtilitiesFree
Percent purity calculator
pure mass over sample mass, free
P
POST /chem/percent-purity$0.002⚙️ Developer UtilitiesFree
Percent solution prep calculator
solute and solvent mass free
A
POST /chem/percent-solution-prep$0.002⚙️ Developer UtilitiesFree
Mass percent to molarity calculator
% w/w, density & MM to M
A
POST /chem/percent-w-w-to-molarity$0.002⚙️ Developer UtilitiesFree
Percent yield calculator
actual vs theoretical product mass, free
P
POST /chem/percent-yield-from-masses$0.002⚙️ Developer UtilitiesFree
pH calculator
pH from hydrogen ion concentration [H+], free
P
POST /chem/ph-from-concentration$0.002⚙️ Developer UtilitiesFree
pH from pOH calculator
pH = 14 − pOH at 25 °C, free
P
POST /chem/ph-from-poh$0.002⚙️ Developer UtilitiesFree
pH to pOH calculator
pOH, [H+] and [OH−] at 25 °C
A
POST /chem/ph-poh-convert$0.002⚙️ Developer UtilitiesFree
Weak acid pH calculator
approximate pH from concentration and Ka or pKa free
A
POST /chem/ph-weak-acid$0.002⚙️ Developer UtilitiesFree
Weak base pH calculator
pH from concentration and Kb, free
P
POST /chem/ph-weak-base$0.002⚙️ Developer UtilitiesFree
pKb from Kb calculator
pKb = −log10(Kb), free
A
POST /chem/pkb-from-kb$0.002⚙️ Developer UtilitiesFree
pOH calculator
pOH and pH from [OH−] at 25 °C free
A
POST /chem/poh$0.002⚙️ Developer UtilitiesFree
pOH calculator
pOH from hydroxide ion concentration [OH−], free
P
POST /chem/poh-from-hydroxide$0.002⚙️ Developer UtilitiesFree
PPB to molarity calculator
convert ppb to M with density, free
P
POST /chem/ppb-to-molarity$0.002⚙️ Developer UtilitiesFree
PPM calculator
parts per million from solute mass free
A
POST /chem/ppm-concentration$0.002⚙️ Developer UtilitiesFree
PPM to mg/L calculator
concentration from density free
A
POST /chem/ppm-to-mg-per-liter$0.002⚙️ Developer UtilitiesFree
PPM to molarity calculator
convert ppm and molar mass to mol/L
A
POST /chem/ppm-to-molarity$0.002⚙️ Developer UtilitiesFree
PPM to PPB converter
parts per million to billion and trillion
A
POST /chem/ppm-to-ppb$0.002⚙️ Developer UtilitiesFree
Pseudo-first-order rate constant calculator
k' from k and excess, free
A
POST /chem/pseudo-first-order$0.002⚙️ Developer UtilitiesFree
Radioactive decay calculator
remaining quantity N(t)=N0·e^(−λt) free
A
POST /chem/radioactive-decay$0.002⚙️ Developer UtilitiesFree
Raoult's law vapor pressure calculator
P = x·P° free
A
POST /chem/raoult-law-vapor-pressure$0.002⚙️ Developer UtilitiesFree
Raoult's law two-component calculator
P = x₁P₁° + x₂P₂° free
A
POST /chem/raoult-two-component$0.002⚙️ Developer UtilitiesFree
Rate constant at new temperature calculator
Arrhenius k2, free
P
POST /chem/rate-constant-new-temperature$0.002⚙️ Developer UtilitiesFree
Rate from stoichiometry calculator
reaction rate from species rate and coefficient, free
A
POST /chem/rate-from-stoichiometry$0.002⚙️ Developer UtilitiesFree
Rate law calculator
reaction rate from k and concentrations, free
A
POST /chem/rate-law$0.002⚙️ Developer UtilitiesFree
Reactant mass needed calculator
grams for a target product, free
A
POST /chem/reactant-mass-for-product$0.002⚙️ Developer UtilitiesFree
Reaction quotient Q calculator
Qc from concentrations and coefficients, free
P
POST /chem/reaction-quotient$0.002⚙️ Developer UtilitiesFree
Reaction rate calculator
average rate from Δconcentration and time, free
P
POST /chem/reaction-rate$0.002⚙️ Developer UtilitiesFree
Reduced properties calculator
Pr, Tr, Vr from critical constants
P
POST /chem/reduced-state-variables$0.002⚙️ Developer UtilitiesFree
Relative vapor pressure lowering calculator
ΔP/P° free
A
POST /chem/relative-vapor-lowering$0.002⚙️ Developer UtilitiesFree
Reverse osmosis net driving pressure
applied P minus feed osmotic π
P
POST /chem/reverse-osmosis-pressure$0.002⚙️ Developer UtilitiesFree
Root-mean-square speed calculator
v_rms from molar mass and T, free
P
POST /chem/rms-speed$0.002⚙️ Developer UtilitiesFree
Second-order concentration calculator
remaining [A] from k, A₀, t, free
A
POST /chem/second-order-concentration$0.002⚙️ Developer UtilitiesFree
Second-order half-life calculator
t½ = 1/(k·[A]₀), free
P
POST /chem/second-order-half-life$0.002⚙️ Developer UtilitiesFree
Serial dilution calculator
concentration at each step free
A
POST /chem/serial-dilution$0.002⚙️ Developer UtilitiesFree
First-order shelf-life calculator
t90 for 10% decomposition, free
P
POST /chem/shelf-life-first-order$0.002⚙️ Developer UtilitiesFree
Solution density from mass percent
ideal mixture estimate, free
A
POST /chem/solution-density-from-percent$0.002⚙️ Developer UtilitiesFree
Solution freezing point calculator
Tf from solvent, molality, Kf and van't Hoff
P
POST /chem/solution-freezing-point$0.002⚙️ Developer UtilitiesFree
Standard cell potential calculator
E° from cathode & anode, free
A
POST /chem/standard-cell-potential$0.002⚙️ Developer UtilitiesFree
Stoichiometric air-fuel ratio calculator
AFR from C and H, free
A
POST /chem/stoichiometric-air-fuel-ratio$0.002⚙️ Developer UtilitiesFree
Mole ratio calculator
product moles from stoichiometric coefficients free
A
POST /chem/stoichiometry-mole-ratio$0.002⚙️ Developer UtilitiesFree
Theoretical yield calculator
moles × stoichiometric ratio, free
A
POST /chem/theoretical-yield$0.002⚙️ Developer UtilitiesFree
Titration equivalence point volume calculator
Veq from C and V
A
POST /chem/titration-equivalence-volume$0.002⚙️ Developer UtilitiesFree
Titration pH at equivalence calculator
salt C and Kb, free
P
POST /chem/titration-ph-at-equivalence$0.002⚙️ Developer UtilitiesFree
Van der Waals molar volume calculator
real gas Vm from P, T, a, b
P
POST /chem/van-der-waals-volume$0.002⚙️ Developer UtilitiesFree
Van't Hoff factor calculator
i from ions and dissociation, free
A
POST /chem/vant-hoff-factor$0.002⚙️ Developer UtilitiesFree
Vapor phase composition calculator
Raoult y_i from x_i and P_i^sat, free
A
POST /chem/vapor-phase-composition$0.002⚙️ Developer UtilitiesFree
Vapor pressure lowering calculator
ΔP = x·P° from mole fraction and pure solvent pressure
P
POST /chem/vapor-pressure-lowering$0.002⚙️ Developer UtilitiesFree
Volume for target molarity calculator
V = n/M from moles, free
P
POST /chem/volume-for-target-molarity$0.002⚙️ Developer UtilitiesFree
Volume percent to molarity calculator
M from % v/v free
A
POST /chem/volume-percent-to-molarity$0.002⚙️ Developer UtilitiesFree
Gas volume to moles calculator
convert STP gas volume to moles free
A
POST /chem/volume-to-moles-gas$0.002⚙️ Developer UtilitiesFree
Weight/volume percent calculator
% w/v from grams and mL, free
A
POST /chem/weight-volume-percent$0.002⚙️ Developer UtilitiesFree
Weight-volume % to molarity calculator
% w/v to M, free
P
POST /chem/weight-volume-to-molarity$0.002⚙️ Developer UtilitiesFree
Precipitation ion product calculator
Q vs Ksp, free
A
POST /chem/will-precipitate$0.002⚙️ Developer UtilitiesFree
Analogous color generator
two neighbors by hue shift angle, free palette
A
POST /color/analogous$0.002⚙️ Developer UtilitiesFree
CMYK to RGB converter
cyan magenta yellow key free
A
POST /color/cmyk-rgb$0.002⚙️ Developer UtilitiesFree
Complementary color finder
opposite hue on the wheel, free
A
POST /color/complementary$0.002⚙️ Developer UtilitiesFree
Color to grayscale converter
luminosity hex & gray value, free
P
POST /color/grayscale$0.002⚙️ Developer UtilitiesFree
Hex to HSL converter
hue, saturation, lightness free
A
POST /color/hex-hsl$0.002⚙️ Developer UtilitiesFree
Hex to color name
nearest CSS named color for any hex code, free
A
POST /color/hex-name$0.002⚙️ Developer UtilitiesFree
Hex to RGB converter
#RRGGBB to red, green, blue, free
P
POST /color/hex-rgb$0.002⚙️ Developer UtilitiesFree
HSL to HSV converter
convert hue saturation lightness and value both ways, free
A
POST /color/hsl-hsv$0.002⚙️ Developer UtilitiesFree
HSL to RGB converter
hue, saturation, lightness to red green blue 0–255, free
A
POST /color/hsl-rgb$0.002⚙️ Developer UtilitiesFree
HSV to RGB converter
hue, saturation, value to red, green, blue, free
P
POST /color/hsv-rgb$0.002⚙️ Developer UtilitiesFree
Color lightener
lighten a hex color by percentage, free HSL tool
A
POST /color/lighten$0.002⚙️ Developer UtilitiesFree
Color mixer
blend two hex colours by ratio, free
A
POST /color/mix$0.002⚙️ Developer UtilitiesFree
CSS color name to hex
tomato, navy, rebeccapurple to #RRGGBB, free
P
POST /color/name-hex$0.002⚙️ Developer UtilitiesFree
RGB to HSL converter
hue, saturation, lightness free
A
POST /color/rgb-hsl$0.002⚙️ Developer UtilitiesFree
RGB to decimal integer
24-bit color pack free
A
POST /color/rgb-int$0.002⚙️ Developer UtilitiesFree
Color shades generator
tints and shades by stepping HSL lightness, free
A
POST /color/shades$0.002⚙️ Developer UtilitiesFree
Triadic color scheme generator
three hues at 120°, free
P
POST /color/triadic$0.002⚙️ Developer UtilitiesFree
Combinations calculator
n choose r (binomial coefficient)
P
POST /combo/combinations$0.002⚙️ Developer UtilitiesFree
Integer compositions calculator
ordered partitions into positive parts
P
POST /combo/compositions$0.002⚙️ Developer UtilitiesFree
Derangement calculator
subfactorial !n, no fixed points
A
POST /combo/derangement$0.002⚙️ Developer UtilitiesFree
Multinomial coefficient calculator
n! / (n1! n2! … nk!)
P
POST /combo/multinomial$0.002⚙️ Developer UtilitiesFree
Integer partition calculator
p(n) ways to sum, free
A
POST /combo/partition-count$0.002⚙️ Developer UtilitiesFree
Pascal's triangle generator
first n rows with exact BigInt entries
A
POST /combo/pascal-triangle$0.002⚙️ Developer UtilitiesFree
Permutations calculator
P(n,r) = n!/(n−r)! with BigInt
A
POST /combo/permutations$0.002⚙️ Developer UtilitiesFree
Permutations with repetition
n^r ordered selections, free
A
POST /combo/permutations-with-repetition$0.002⚙️ Developer UtilitiesFree
Round-robin matches calculator
games and rounds for n teams
A
POST /combo/round-robin$0.002⚙️ Developer UtilitiesFree
Stirling numbers of the second kind
S(n,k) partitions, free
A
POST /combo/stirling-second$0.002⚙️ Developer UtilitiesFree
Acres to square meters converter
exact factor, free
P
POST /conv/acres-to-square-meters$0.002⚙️ Developer UtilitiesFree
Physical action converter
J·s, eV·s, erg·s, h, ħ, free
P
POST /conv/action-physics$0.002⚙️ Developer UtilitiesFree
Water alkalinity converter
mg/L CaCO3, meq/L, dKH, free
A
POST /conv/alkalinity$0.002⚙️ Developer UtilitiesFree
Angular momentum converter
kg·m²/s, g·cm²/s, J·s, free
A
POST /conv/angular-momentum$0.002⚙️ Developer UtilitiesFree
API gravity converter
°API, specific gravity and density, free
P
POST /conv/api-gravity$0.002⚙️ Developer UtilitiesFree
ATM to PSI converter
exact atmosphere factor, free
P
POST /conv/atm-to-psi$0.002⚙️ Developer UtilitiesFree
Beaufort scale converter
force, knots, mph, m/s, free
P
POST /conv/beaufort-wind$0.002⚙️ Developer UtilitiesFree
Belt size converter
waist in/cm, numeric belt & letter, free
P
POST /conv/belt-size$0.002⚙️ Developer UtilitiesFree
Binary prefix converter
kibi, mebi, gibi vs kilo, free
A
POST /conv/binary-prefix$0.002⚙️ Developer UtilitiesFree
BTU to kWh converter
exact International Table factor, free
P
POST /conv/btu-to-kwh$0.002⚙️ Developer UtilitiesFree
Calories to joules converter
exact 4.184 factor, free
P
POST /conv/calories-to-joules$0.002⚙️ Developer UtilitiesFree
Calorific value converter
MJ/m³, BTU/ft³, kcal/L, free
P
POST /conv/calorific-value$0.002⚙️ Developer UtilitiesFree
CM to inches converter
exact 2.54 factor, free
P
POST /conv/cm-to-inches$0.002⚙️ Developer UtilitiesFree
Color depth converter
bpp, colors, bits/channel, free
A
POST /conv/color-depth$0.002⚙️ Developer UtilitiesFree
Cubic meters to cubic feet converter
exact factor, free
P
POST /conv/cubic-meters-to-cubic-feet$0.002⚙️ Developer UtilitiesFree
Degrees to gradians converter
exact deg × 10/9, free
P
POST /conv/degrees-to-gradians$0.002⚙️ Developer UtilitiesFree
Didot point converter
cicero, mm and PostScript points, free
A
POST /conv/didot-point$0.002⚙️ Developer UtilitiesFree
Electric flux converter
V·m, N·m²/C, C/ε₀, statV·cm, free
P
POST /conv/electric-flux$0.002⚙️ Developer UtilitiesFree
Electron mobility converter
m²/(V·s), cm²/(V·s), free
P
POST /conv/electron-mobility$0.002⚙️ Developer UtilitiesFree
Entropy converter
J/K, cal/K, BTU/R and more, free
P
POST /conv/entropy$0.002⚙️ Developer UtilitiesFree
Equivalent weight converter
g/eq, kg/eq, mg/meq, free
A
POST /conv/equivalent-weight$0.002⚙️ Developer UtilitiesFree
Fabric weight converter
gsm, oz/yd², oz/ft², free
A
POST /conv/fabric-weight$0.002⚙️ Developer UtilitiesFree
Fahrenheit to Rankine converter
exact F+459.67, free
P
POST /conv/fahrenheit-to-rankine$0.002⚙️ Developer UtilitiesFree
Film speed converter
ISO, ASA, DIN and more, free
A
POST /conv/film-speed$0.002⚙️ Developer UtilitiesFree
Foot-pounds to newton-meters converter
exact factor, free
P
POST /conv/foot-pounds-to-newton-meters$0.002⚙️ Developer UtilitiesFree
Gallons to cups converter
exact US factor, free
P
POST /conv/gallons-to-cups$0.002⚙️ Developer UtilitiesFree
Gallons to quarts converter
exact US factor, free
P
POST /conv/gallons-to-quarts$0.002⚙️ Developer UtilitiesFree
Glove size converter
cm, inches and numeric size, free
A
POST /conv/glove-size$0.002⚙️ Developer UtilitiesFree
Hardness scale converter
Rockwell, Brinell, Vickers, free
P
POST /conv/hardness$0.002⚙️ Developer UtilitiesFree
Hectares to acres converter
exact factor, free
P
POST /conv/hectares-to-acres$0.002⚙️ Developer UtilitiesFree
Humidity ratio converter
kg/kg, grains/lb, g/kg and more, free
P
POST /conv/humidity-ratio$0.002⚙️ Developer UtilitiesFree
Hydraulic conductivity converter
m/s, cm/h, gpd/ft², free
A
POST /conv/hydraulic-conductivity$0.002⚙️ Developer UtilitiesFree
Imperial gallons to US gallons converter
exact factor, free
P
POST /conv/imperial-gallons-to-us-gallons$0.002⚙️ Developer UtilitiesFree
Inches to cm converter
convert inches to centimeters, free
A
POST /conv/inches-to-cm$0.002⚙️ Developer UtilitiesFree
Jerk converter
m/s³, ft/s³, g/s and more, free
P
POST /conv/jerk$0.002⚙️ Developer UtilitiesFree
Joules to foot-pounds converter
exact factor, free
P
POST /conv/joules-to-foot-pounds$0.002⚙️ Developer UtilitiesFree
kg/m³ to lb/ft³ converter
exact density factor, free
P
POST /conv/kg-per-m3-to-lb-per-ft3$0.002⚙️ Developer UtilitiesFree
KG to stone converter
exact factor, free in browser
P
POST /conv/kg-to-stone$0.002⚙️ Developer UtilitiesFree
KM to miles converter
exact factor, free in browser
P
POST /conv/km-to-miles$0.002⚙️ Developer UtilitiesFree
Knots to km/h converter
exact 1.852 factor, free in browser
P
POST /conv/knots-to-kmh$0.002⚙️ Developer UtilitiesFree
kW to hp converter
exact mechanical horsepower factor, free
P
POST /conv/kw-to-hp$0.002⚙️ Developer UtilitiesFree
Lbs to ounces converter
exact 16 oz factor, free
P
POST /conv/lbs-to-ounces$0.002⚙️ Developer UtilitiesFree
Vacuum leak rate converter
mbar·L/s, sccm, atm·cc/s, free
P
POST /conv/leak-rate$0.002⚙️ Developer UtilitiesFree
Linear mass density converter
kg/m, g/m, lb/ft and more, free
P
POST /conv/linear-density$0.002⚙️ Developer UtilitiesFree
Linear energy transfer converter
keV/μm, MeV/cm, J/m, free
P
POST /conv/linear-energy-transfer$0.002⚙️ Developer UtilitiesFree
Nominal lumber size converter
actual inches & mm, free
P
POST /conv/lumber-size$0.002⚙️ Developer UtilitiesFree
Luminous energy converter
lm·s, talbot, lm·h, free
A
POST /conv/luminous-energy$0.002⚙️ Developer UtilitiesFree
Luminous exposure converter
lux·s, lux·h, phot·s, free
P
POST /conv/luminous-exposure$0.002⚙️ Developer UtilitiesFree
Magnetic moment converter
A·m², μB, erg/G, J/T, free
P
POST /conv/magnetic-moment$0.002⚙️ Developer UtilitiesFree
Magnetic susceptibility converter
SI/CGS volume, mass & molar, free
A
POST /conv/magnetic-susceptibility$0.002⚙️ Developer UtilitiesFree
Magnetomotive force converter
ampere-turns, gilberts, abampere-turns, free
A
POST /conv/magnetomotive-force$0.002⚙️ Developer UtilitiesFree
Mass diffusivity converter
m²/s, cm²/s, ft²/h, free
A
POST /conv/mass-diffusivity$0.002⚙️ Developer UtilitiesFree
Mass flux converter
kg/(m²·s), g/(cm²·s) and more, free
P
POST /conv/mass-flux$0.002⚙️ Developer UtilitiesFree
Meters per second to mph
exact factor, free in browser
P
POST /conv/meters-per-second-to-mph$0.002⚙️ Developer UtilitiesFree
Meters to inches converter
exact factor, free in browser
P
POST /conv/meters-to-inches$0.002⚙️ Developer UtilitiesFree
Meters to yards converter
exact factor, free in browser
P
POST /conv/meters-to-yards$0.002⚙️ Developer UtilitiesFree
Metric tons to US tons converter
exact factor, free in browser
P
POST /conv/metric-tons-to-us-tons$0.002⚙️ Developer UtilitiesFree
Miles to yards converter
exact factor, free in browser
P
POST /conv/miles-to-yards$0.002⚙️ Developer UtilitiesFree
ML to teaspoons converter
exact 5 ml factor, free
P
POST /conv/ml-to-teaspoons$0.002⚙️ Developer UtilitiesFree
Molar conductivity converter
S·m²/mol, S·cm²/mol, free
A
POST /conv/molar-conductivity$0.002⚙️ Developer UtilitiesFree
Molar entropy converter
J/(mol·K), cal/(mol·K), eu, free
A
POST /conv/molar-entropy$0.002⚙️ Developer UtilitiesFree
Molar flow rate converter
mol/s, mol/h, kmol/h, free
A
POST /conv/molar-flow-rate$0.002⚙️ Developer UtilitiesFree
Molar volume converter
m³/mol, L/mol, mL/mol and more, free
P
POST /conv/molar-volume$0.002⚙️ Developer UtilitiesFree
Nuclear cross section converter
barn, m², cm², free
A
POST /conv/nuclear-cross-section$0.002⚙️ Developer UtilitiesFree
Numerical aperture converter
NA, f-number and acceptance angle, free
A
POST /conv/numerical-aperture$0.002⚙️ Developer UtilitiesFree
Parsecs to light-years converter
exact IAU factor, free
P
POST /conv/parsecs-to-light-years$0.002⚙️ Developer UtilitiesFree
Permeability converter
darcy, millidarcy, m² and more, free
P
POST /conv/permeability-darcy$0.002⚙️ Developer UtilitiesFree
Permittivity converter
F/m, ε_r, pF/m, free
A
POST /conv/permittivity$0.002⚙️ Developer UtilitiesFree
Photon energy converter
eV, nm wavelength, THz, free
A
POST /conv/photon-energy$0.002⚙️ Developer UtilitiesFree
Pressure unit converter
Pa, kPa, bar, atm, psi, mmHg and torr, free
A
POST /conv/pressure$0.002⚙️ Developer UtilitiesFree
Pressure altitude converter
hPa, inHg, meters and more, free
A
POST /conv/pressure-altitude$0.002⚙️ Developer UtilitiesFree
Pressure head converter
mH2O, ftH2O, psi and more, free
A
POST /conv/pressure-head$0.002⚙️ Developer UtilitiesFree
Rainfall rate converter
mm/h, in/h, L/m²/h, free
A
POST /conv/rainfall-rate$0.002⚙️ Developer UtilitiesFree
Audio sample rate converter
Hz, kHz, sps, free
P
POST /conv/sample-rate$0.002⚙️ Developer UtilitiesFree
Screw gauge size converter
US #, mm & inch diameter, free
P
POST /conv/screw-size$0.002⚙️ Developer UtilitiesFree
Section modulus converter
m³, cm³, mm³, in³, free
A
POST /conv/section-modulus$0.002⚙️ Developer UtilitiesFree
Sheet metal gauge converter
gauge, mm, inches, free
A
POST /conv/sheet-metal-gauge$0.002⚙️ Developer UtilitiesFree
Shutter speed converter
fraction, seconds, stops, free
A
POST /conv/shutter-speed$0.002⚙️ Developer UtilitiesFree
Sieve mesh size converter
US, Tyler, micron, free
A
POST /conv/sieve-mesh$0.002⚙️ Developer UtilitiesFree
Solar mass, radius & luminosity converter
SI units, free
A
POST /conv/solar-units$0.002⚙️ Developer UtilitiesFree
Sound absorption converter
sabins ↔ metric sabins ↔ m², free
A
POST /conv/sound-absorption$0.002⚙️ Developer UtilitiesFree
Sound power converter
W, dB re 1 pW, BTU/h, free
P
POST /conv/sound-power$0.002⚙️ Developer UtilitiesFree
Specific impulse converter
seconds, m/s exhaust velocity, lbf·s/lb, free
P
POST /conv/specific-impulse$0.002⚙️ Developer UtilitiesFree
Square km to square miles
exact factor, free in browser
P
POST /conv/square-km-to-square-miles$0.002⚙️ Developer UtilitiesFree
Spring stiffness converter
N/m, lbf/in, kg/mm, free
A
POST /conv/stiffness$0.002⚙️ Developer UtilitiesFree
Guitar string gauge converter
mils, mm & inches, free
P
POST /conv/string-gauge$0.002⚙️ Developer UtilitiesFree
Surface charge density converter
C/m², C/cm², C/in², free
A
POST /conv/surface-charge-density$0.002⚙️ Developer UtilitiesFree
Thermal conductance converter
W/K, BTU/(h·°F), cal/(s·K), free
P
POST /conv/thermal-conductance$0.002⚙️ Developer UtilitiesFree
Thermal expansion coefficient converter
1/K, ppm/K, 1/°F, free
A
POST /conv/thermal-expansion-coefficient$0.002⚙️ Developer UtilitiesFree
Thread count converter
TPI, threads/cm, per 10 cm and more, free
P
POST /conv/thread-count$0.002⚙️ Developer UtilitiesFree
Thread pitch converter
TPI, mm pitch and threads/cm, free
A
POST /conv/thread-pitch$0.002⚙️ Developer UtilitiesFree
Torr to PSI converter
exact torr factor, free
P
POST /conv/torr-to-psi$0.002⚙️ Developer UtilitiesFree
Turbidity converter
NTU, FNU, FTU, JTU, free
P
POST /conv/turbidity$0.002⚙️ Developer UtilitiesFree
Vacuum pressure converter
torr, mbar, Pa, micron, free
P
POST /conv/vacuum$0.002⚙️ Developer UtilitiesFree
Water conductivity & TDS converter
µS/cm, ppm, gpg, free
A
POST /conv/water-conductivity$0.002⚙️ Developer UtilitiesFree
Cups to grams converter
flour, sugar, butter and more by ingredient density, free
A
POST /cook/cups-grams$0.002⚙️ Developer UtilitiesFree
Fluid ounces to ml converter
US and imperial fl oz ↔ milliliters, free
A
POST /cook/fl-oz-ml$0.002⚙️ Developer UtilitiesFree
Flour cups to grams converter
all-purpose, bread & cake, free
P
POST /cook/flour$0.002⚙️ Developer UtilitiesFree
Gas mark converter
oven °C & °F from Gas Mark, free
P
POST /cook/gas-mark$0.002⚙️ Developer UtilitiesFree
Grams to cups converter
by ingredient density, free
A
POST /cook/grams-cups$0.002⚙️ Developer UtilitiesFree
mL to cups converter
US, metric & imperial cups, free
A
POST /cook/ml-cups$0.002⚙️ Developer UtilitiesFree
Oven temperature converter
Celsius, Fahrenheit and oven heat labels, free
A
POST /cook/oven-temp$0.002⚙️ Developer UtilitiesFree
Cooking ounces to grams converter
kitchen weight oz ↔ g, free
A
POST /cook/oz-grams$0.002⚙️ Developer UtilitiesFree
Quarts to liters converter
US & imperial quarts, free
A
POST /cook/quarts-liters$0.002⚙️ Developer UtilitiesFree
Recipe scaler
scale ingredient amounts by servings or multiplier, free
P
POST /cook/recipe-scale$0.002⚙️ Developer UtilitiesFree
Rice cups to grams converter
raw or cooked, free
A
POST /cook/rice$0.002⚙️ Developer UtilitiesFree
Sugar cups to grams converter
granulated, brown and powdered by density, free
A
POST /cook/sugar$0.002⚙️ Developer UtilitiesFree
Tablespoons to ml converter
US, metric & Australian tbsp, free
P
POST /cook/tbsp-ml$0.002⚙️ Developer UtilitiesFree
US to metric cooking converter
cups, tbsp, fl oz ↔ ml, g, free
A
POST /cook/us-metric$0.002⚙️ Developer UtilitiesFree
Yeast conversion converter
active dry, instant & fresh, free
A
POST /cook/yeast$0.002⚙️ Developer UtilitiesFree
Add days to a date
ISO calendar date plus or minus N days, free
A
POST /date/add-days$0.002⚙️ Developer UtilitiesFree
Add years to a date
ISO calendar date plus or minus N years, free
A
POST /date/add-years$0.002⚙️ Developer UtilitiesFree
Birth flower by month
traditional birth flowers for each month
P
POST /date/birth-flower$0.002⚙️ Developer UtilitiesFree
Chinese zodiac element calculator
animal + five-element year in the 60-year cycle, free
A
POST /date/chinese-zodiac-element$0.002⚙️ Developer UtilitiesFree
Countdown between two dates
days hours minutes seconds, free
A
POST /date/countdown-between$0.002⚙️ Developer UtilitiesFree
Day of year to date converter
ordinal 1–366 to calendar YYYY-MM-DD, free
A
POST /date/date-from-dayofyear$0.002⚙️ Developer UtilitiesFree
Day of the week calculator
name and number from an ISO date
P
POST /date/day-of-week$0.002⚙️ Developer UtilitiesFree
Day of the year calculator
ISO date to ordinal day 1–366, free
A
POST /date/day-of-year$0.002⚙️ Developer UtilitiesFree
Days in a month calculator
leap years included, free
A
POST /date/days-in-month$0.002⚙️ Developer UtilitiesFree
Days left in the year
remaining days until December 31, free
P
POST /date/days-remaining-year$0.002⚙️ Developer UtilitiesFree
Decade and century finder
year to 2020s & 21st, free
A
POST /date/decade-century$0.002⚙️ Developer UtilitiesFree
Dominical letter calculator
Gregorian A–G (or two letters in leap years), free
A
POST /date/dominical-letter$0.002⚙️ Developer UtilitiesFree
Doomsday rule calculator
Conway weekday from ISO date, free
A
POST /date/doomsday-weekday$0.002⚙️ Developer UtilitiesFree
Orthodox Easter date calculator
Julian computus to Gregorian, free
A
POST /date/easter-orthodox$0.002⚙️ Developer UtilitiesFree
Friday the 13th finder
every Friday the 13th in a year, free
P
POST /date/friday-13th$0.002⚙️ Developer UtilitiesFree
Humanize duration
seconds to days, hours, minutes (readable)
P
POST /date/humanize-duration$0.002⚙️ Developer UtilitiesFree
Leap year checker
Gregorian leap test and divisibility reason
P
POST /date/is-leap-year$0.002⚙️ Developer UtilitiesFree
ISO weekday number
Monday=1 to Sunday=7 from an ISO date
P
POST /date/iso-weekday-number$0.002⚙️ Developer UtilitiesFree
Julian Day Number calculator
ISO date to astronomical JDN, free
A
POST /date/julian-day-number$0.002⚙️ Developer UtilitiesFree
Last weekday of the month
final Monday–Sunday date, free
P
POST /date/last-weekday-of-month$0.002⚙️ Developer UtilitiesFree
Leap years in a range
count and list Gregorian leap years between two years, free
A
POST /date/leap-years-between$0.002⚙️ Developer UtilitiesFree
Printable month calendar generator
weeks layout, free
A
POST /date/month-calendar$0.002⚙️ Developer UtilitiesFree
Months between two dates
whole months and remaining days, free
A
POST /date/months-between$0.002⚙️ Developer UtilitiesFree
Nth weekday of the month
third Monday, last Friday and any ordinal date, free
A
POST /date/nth-weekday-of-month$0.002⚙️ Developer UtilitiesFree
ISO ordinal date converter
YYYY-MM-DD ↔ YYYY-DDD, free
A
POST /date/ordinal-date$0.002⚙️ Developer UtilitiesFree
Previous weekday occurrence
most recent Monday–Sunday before a date, free
P
POST /date/previous-weekday$0.002⚙️ Developer UtilitiesFree
Calendar quarter finder
ISO date to Q1–Q4 with start and end dates, free
A
POST /date/quarter-of-year$0.002⚙️ Developer UtilitiesFree
Quarter start and end dates
Q1–Q4 calendar range, free
A
POST /date/quarter-start-end$0.002⚙️ Developer UtilitiesFree
Recurring dates generator
every N days from start to end, free
A
POST /date/recurring-dates$0.002⚙️ Developer UtilitiesFree
Season of the year calculator
meteorological season by hemisphere
P
POST /date/season$0.002⚙️ Developer UtilitiesFree
US week number calculator
Sunday start, week 1 has Jan 1
A
POST /date/us-week-number$0.002⚙️ Developer UtilitiesFree
Week start and end dates
ISO date plus first weekday to Monday–Sunday range, free
A
POST /date/week-start-end$0.002⚙️ Developer UtilitiesFree
Weekday count in a year
how many Mondays, free
A
POST /date/weekday-frequency$0.002⚙️ Developer UtilitiesFree
Weekend days between two dates
count Saturdays and Sundays in a date range, free
A
POST /date/weekend-count$0.002⚙️ Developer UtilitiesFree
Weeks between two dates
whole weeks and leftover days from ISO dates, free
A
POST /date/weeks-between$0.002⚙️ Developer UtilitiesFree
Year progress percentage
ISO date to % of calendar year elapsed, free
A
POST /date/year-progress$0.002⚙️ Developer UtilitiesFree
Zeller's congruence calculator
weekday from ISO date, step by step
P
POST /date/zeller-weekday$0.002⚙️ Developer UtilitiesFree
Zodiac element calculator
birth date to fire, earth, air, water
A
POST /date/zodiac-element$0.002⚙️ Developer UtilitiesFree
Western zodiac sign calculator
birth date to sign, free
A
POST /date/zodiac-sign$0.002⚙️ Developer UtilitiesFree
AWG ampacity calculator
max safe current by wire gauge
A
POST /elec/awg-ampacity$0.002⚙️ Developer UtilitiesFree
AWG wire gauge calculator
diameter, area and ohms per metre, free
A
POST /elec/awg-wire$0.002⚙️ Developer UtilitiesFree
Battery life calculator
runtime hours from mAh capacity and mA draw, free
A
POST /elec/battery-life$0.002⚙️ Developer UtilitiesFree
Capacitive reactance calculator
Xc=1/(2πfC) in ohms, free
A
POST /elec/capacitive-reactance$0.002⚙️ Developer UtilitiesFree
Capacitor charge calculator
Q=CV stored charge from C and V, free
A
POST /elec/capacitor-charge$0.002⚙️ Developer UtilitiesFree
Capacitor charging calculator
V(t)=Vs(1−e^(−t/RC)) voltage during charge, free
A
POST /elec/capacitor-charge-time$0.002⚙️ Developer UtilitiesFree
Parallel capacitance calculator
total C for capacitors in parallel
A
POST /elec/capacitors-parallel$0.002⚙️ Developer UtilitiesFree
Series capacitance calculator
capacitors in series, free
P
POST /elec/capacitors-series$0.002⚙️ Developer UtilitiesFree
Electric charge calculator
Q=It solve charge, current or time
A
POST /elec/charge-current-time$0.002⚙️ Developer UtilitiesFree
Coulomb's law calculator
electrostatic force between two charges
A
POST /elec/coulombs-law$0.002⚙️ Developer UtilitiesFree
Current divider calculator
branch currents for two parallel resistors, free
A
POST /elec/current-divider$0.002⚙️ Developer UtilitiesFree
Electric field force calculator
F = qE, free in browser
P
POST /elec/electric-field-force$0.002⚙️ Developer UtilitiesFree
Electric field calculator
E=kQ/r² point charge magnitude, free
A
POST /elec/electric-field-point$0.002⚙️ Developer UtilitiesFree
Electricity cost calculator
appliance energy use and running cost
A
POST /elec/electrical-energy-cost$0.002⚙️ Developer UtilitiesFree
Frequency period converter
T = 1/f and f = 1/T, free
A
POST /elec/frequency-period$0.002⚙️ Developer UtilitiesFree
Inductive reactance calculator
XL = 2πfL in ohms, free
P
POST /elec/inductive-reactance$0.002⚙️ Developer UtilitiesFree
LC resonant frequency calculator
f₀ = 1/(2π√(LC)), free
P
POST /elec/lc-resonant-frequency$0.002⚙️ Developer UtilitiesFree
LED resistor calculator
series resistor and power rating
A
POST /elec/led-resistor$0.002⚙️ Developer UtilitiesFree
Magnetic field of a straight wire calculator
B = μ₀I/(2πr), free
P
POST /elec/magnetic-field-wire$0.002⚙️ Developer UtilitiesFree
Magnetic force calculator
Lorentz F=qvB sinθ on a moving charge, free
A
POST /elec/magnetic-force-charge$0.002⚙️ Developer UtilitiesFree
Force on a current-carrying wire calculator
F = I L B sin(θ)
A
POST /elec/magnetic-force-wire$0.002⚙️ Developer UtilitiesFree
555 timer calculator
astable frequency and duty cycle
A
POST /elec/ne555-astable$0.002⚙️ Developer UtilitiesFree
555 timer monostable calculator
pulse width t=1.1RC, free
A
POST /elec/ne555-monostable$0.002⚙️ Developer UtilitiesFree
Non-inverting amplifier calculator
gain Av = 1 + Rf/Rg, free
P
POST /elec/op-amp-noninverting$0.002⚙️ Developer UtilitiesFree
Parallel-plate capacitor calculator
C from area, gap and dielectric
A
POST /elec/parallel-plate-capacitance$0.002⚙️ Developer UtilitiesFree
Power gain dB calculator
G = 10·log10(Pout/Pin) from input and output power, free
A
POST /elec/power-gain-db$0.002⚙️ Developer UtilitiesFree
PWM duty cycle calculator
on-time, period, average voltage, free
P
POST /elec/pwm-duty-cycle$0.002⚙️ Developer UtilitiesFree
RC filter cutoff calculator
fc = 1/(2πRC) for LP/HP filters
A
POST /elec/rc-filter-cutoff$0.002⚙️ Developer UtilitiesFree
RC time constant calculator
τ=RC and 5τ settling time, free
A
POST /elec/rc-time-constant$0.002⚙️ Developer UtilitiesFree
Wire resistance calculator
R = ρL/A from resistivity, free
P
POST /elec/resistivity$0.002⚙️ Developer UtilitiesFree
Series resistance calculator
total ohms for resistors in series, free
A
POST /elec/resistors-series$0.002⚙️ Developer UtilitiesFree
RL filter cutoff calculator
fc=R/(2πL) in hertz, free
A
POST /elec/rl-filter-cutoff$0.002⚙️ Developer UtilitiesFree
RL time constant calculator
τ = L/R for series RL circuits
A
POST /elec/rl-time-constant$0.002⚙️ Developer UtilitiesFree
Slew rate from full-power bandwidth
SR=2πfVpeak op-amp calculator, free
A
POST /elec/slew-rate-bandwidth$0.002⚙️ Developer UtilitiesFree
Johnson noise calculator
RMS thermal noise voltage √(4kTRΔf), free
A
POST /elec/thermal-noise$0.002⚙️ Developer UtilitiesFree
Voltage drop calculator
AWG wire, length, current, free
P
POST /elec/voltage-drop-wire$0.002⚙️ Developer UtilitiesFree
Voltage gain dB calculator
Av = 20·log10(Vout/Vin)
A
POST /elec/voltage-gain-db$0.002⚙️ Developer UtilitiesFree
Watts to dBm calculator
convert power in W or mW to dBm, free
A
POST /elec/watts-to-dbm$0.002⚙️ Developer UtilitiesFree
Watts, volts & amps calculator
solve power, voltage or current
A
POST /elec/watts-volts-amps$0.002⚙️ Developer UtilitiesFree
Frequency to wavelength calculator
free-space RF λ = c/f, free
P
POST /elec/wavelength-frequency-rf$0.002⚙️ Developer UtilitiesFree
Wheatstone bridge calculator
find unknown resistance Rx, free
P
POST /elec/wheatstone-bridge$0.002⚙️ Developer UtilitiesFree
Zener diode resistor calculator
series resistor value and power rating, free
A
POST /elec/zener-resistor$0.002⚙️ Developer UtilitiesFree
Affine cipher
encrypt or decrypt with keys a and b, free
A
POST /enc/affine$0.002⚙️ Developer UtilitiesFree
ASCII code lookup
character to decimal, hex and octal, free
A
POST /enc/ascii-lookup$0.002⚙️ Developer UtilitiesFree
Atbash cipher
mirror the alphabet (A↔Z), free online
A
POST /enc/atbash$0.002⚙️ Developer UtilitiesFree
Autokey cipher
encrypt or decrypt text with a keyword extended by the message, free
A
POST /enc/autokey$0.002⚙️ Developer UtilitiesFree
Base16 RFC 4648 encoder & decoder
uppercase hex, free
P
POST /enc/base16-rfc4648$0.002⚙️ Developer UtilitiesFree
Base32 encoder & decoder
RFC 4648 A-Z and 2-7, free
A
POST /enc/base32$0.002⚙️ Developer UtilitiesFree
Base58 encoder & decoder
Bitcoin alphabet, free online
P
POST /enc/base58$0.002⚙️ Developer UtilitiesFree
Flickr Base58 encoder & decoder
short URL alphabet, free
P
POST /enc/base58-flickr$0.002⚙️ Developer UtilitiesFree
Text to Base64
encode or decode with standard padding, free
A
POST /enc/base64$0.002⚙️ Developer UtilitiesFree
Ascii85 / Base85 encoder
encode or decode text, free
A
POST /enc/base85$0.002⚙️ Developer UtilitiesFree
Beaufort cipher
encrypt or decrypt text with a keyword, free
A
POST /enc/beaufort$0.002⚙️ Developer UtilitiesFree
Bifid cipher
encrypt or decrypt text with Polybius fractionation and a keyword, free
A
POST /enc/bifid$0.002⚙️ Developer UtilitiesFree
Text to binary converter
8-bit encode & decode, free
P
POST /enc/binary-text$0.002⚙️ Developer UtilitiesFree
Braille translator
text to Unicode Braille (Grade 1) and back, free
A
POST /enc/braille$0.002⚙️ Developer UtilitiesFree
Caesar cipher
encrypt or decrypt text with a letter shift, free
A
POST /enc/caesar$0.002⚙️ Developer UtilitiesFree
Gronsfeld cipher
encrypt & decrypt with a numeric key, free
P
POST /enc/gronsfeld$0.002⚙️ Developer UtilitiesFree
Text to hex converter
encode or decode UTF-8 bytes, free
A
POST /enc/hex-text$0.002⚙️ Developer UtilitiesFree
Keyboard shift cipher
QWERTY adjacent-key encrypt or decrypt, free
A
POST /enc/keyboard-shift$0.002⚙️ Developer UtilitiesFree
Leetspeak translator
convert text to 1337 speak and back, free
A
POST /enc/leetspeak$0.002⚙️ Developer UtilitiesFree
Multiplicative cipher
encrypt & decrypt with a coprime key, free
P
POST /enc/multiplicative$0.002⚙️ Developer UtilitiesFree
NATO phonetic alphabet
spell or decode Alpha Bravo Charlie, free
A
POST /enc/nato$0.002⚙️ Developer UtilitiesFree
Nihilist cipher
encrypt or decrypt with Polybius square keyword and numeric key, free
A
POST /enc/nihilist$0.002⚙️ Developer UtilitiesFree
Text to octal converter
encode UTF-8 bytes as base-8, free
A
POST /enc/octal-text$0.002⚙️ Developer UtilitiesFree
Playfair cipher
encrypt & decrypt with a keyword square, free
P
POST /enc/playfair$0.002⚙️ Developer UtilitiesFree
Polybius square cipher
encrypt or decrypt letters as row-column digit pairs, free
A
POST /enc/polybius$0.002⚙️ Developer UtilitiesFree
Punycode converter
encode Unicode domains to xn--, free
A
POST /enc/punycode$0.002⚙️ Developer UtilitiesFree
Rail fence cipher
encrypt or decrypt zigzag transposition, free
A
POST /enc/rail-fence$0.002⚙️ Developer UtilitiesFree
ROT13 encoder
rotate letters by 13, free online
A
POST /enc/rot13$0.002⚙️ Developer UtilitiesFree
ROT18 cipher
ROT13 letters + ROT5 digits, free online
A
POST /enc/rot18$0.002⚙️ Developer UtilitiesFree
ROT5 digit cipher
rotate 0–9 by five, free online
P
POST /enc/rot5$0.002⚙️ Developer UtilitiesFree
Tap code translator
Polybius encode & decode, free
P
POST /enc/tap-code$0.002⚙️ Developer UtilitiesFree
Trifid cipher
encrypt or decrypt with a 27-symbol cube, free
A
POST /enc/trifid$0.002⚙️ Developer UtilitiesFree
Unicode code point converter
characters ↔ U+XXXX, free
A
POST /enc/unicode-codepoint$0.002⚙️ Developer UtilitiesFree
URL percent encoder & decoder
escape reserved characters, free
A
POST /enc/url$0.002⚙️ Developer UtilitiesFree
UTF-8 byte encoder
text to hex bytes & decode, free
P
POST /enc/utf8-bytes$0.002⚙️ Developer UtilitiesFree
XOR cipher
encrypt or decrypt with a repeating key, free online
A
POST /enc/xor$0.002⚙️ Developer UtilitiesFree
Base62 number converter
integer to or from base-62 (0-9A-Za-z), free
A
POST /fmt/base62$0.002⚙️ Developer UtilitiesFree
Binary to hex converter
base-2 string to base-16 value, free
A
POST /fmt/binary-hex$0.002⚙️ Developer UtilitiesFree
Chinese number converter
everyday & financial numerals
A
POST /fmt/chinese-numerals$0.002⚙️ Developer UtilitiesFree
Number to currency words
spell money for cheque writing (e.g. 1250.50 → one thousand two hundred fifty and 50/100), free
P
POST /fmt/currency-words$0.002⚙️ Developer UtilitiesFree
Decimal to binary converter
whole number to base-2 string, free
A
POST /fmt/decimal-binary$0.002⚙️ Developer UtilitiesFree
Decimal to fraction converter
reduced numerator/denominator, free
A
POST /fmt/decimal-fraction$0.002⚙️ Developer UtilitiesFree
Decimal to octal converter
base-10 to base-8, free
A
POST /fmt/decimal-octal$0.002⚙️ Developer UtilitiesFree
Decimal to percent converter
0.25 to 25%, free online
A
POST /fmt/decimal-percent$0.002⚙️ Developer UtilitiesFree
Duodecimal converter
base-10 ↔ base-12 with dek (X) and el (E), free
A
POST /fmt/duodecimal$0.002⚙️ Developer UtilitiesFree
Fraction to decimal converter
turn a/b into a decimal value, free
A
POST /fmt/fraction-decimal$0.002⚙️ Developer UtilitiesFree
Gray code converter
binary ↔ reflected Gray, free
A
POST /fmt/gray-code$0.002⚙️ Developer UtilitiesFree
Hex to binary converter
base-16 string to base-2 bits, free
P
POST /fmt/hex-binary$0.002⚙️ Developer UtilitiesFree
Hex to decimal converter
base-16 string to integer, free
P
POST /fmt/hex-decimal$0.002⚙️ Developer UtilitiesFree
Float to IEEE-754 converter
hex and binary bit pattern, free
P
POST /fmt/ieee754$0.002⚙️ Developer UtilitiesFree
Spell a number in English
words for integers, decimals, negatives
A
POST /fmt/number-to-words-en$0.002⚙️ Developer UtilitiesFree
Spell a number in Spanish
formal words for any integer, free
A
POST /fmt/number-to-words-es$0.002⚙️ Developer UtilitiesFree
Percent to decimal converter
percentage to decimal (e.g. 25% → 0.25), free
P
POST /fmt/percent-decimal$0.002⚙️ Developer UtilitiesFree
Large Roman numerals converter
vinculum overlines above 3999, free
P
POST /fmt/roman-large$0.002⚙️ Developer UtilitiesFree
Number rounding tool
decimals, nearest ten, hundred or thousand, free
A
POST /fmt/rounding$0.002⚙️ Developer UtilitiesFree
Scientific notation converter
decimal ↔ mantissa×10^n, free
A
POST /fmt/scientific-notation$0.002⚙️ Developer UtilitiesFree
Ordinal words converter
spell 1st, 21st, 100th in English
A
POST /fmt/spell-ordinal$0.002⚙️ Developer UtilitiesFree
Thai numeral converter
Western digits ↔ Thai ๐-๙ integers, free
A
POST /fmt/thai-numerals$0.002⚙️ Developer UtilitiesFree
Add thousands separators
format numbers with grouped digits, free
P
POST /fmt/thousands-separator$0.002⚙️ Developer UtilitiesFree
Two's complement converter
signed integer ↔ fixed-width binary, free
A
POST /fmt/twos-complement$0.002⚙️ Developer UtilitiesFree
Antipode coordinates calculator
opposite point on Earth from lat/lon, free
A
POST /geo/antipode$0.002⚙️ Developer UtilitiesFree
Bearing to compass direction
degrees to N, NNE, NE… free
A
POST /geo/bearing-to-compass$0.002⚙️ Developer UtilitiesFree
Point-radius bounding box
min/max lat lon from center, free
P
POST /geo/bounding-box$0.002⚙️ Developer UtilitiesFree
Cross-track distance calculator
signed offset from a great-circle path, free
A
POST /geo/cross-track-distance$0.002⚙️ Developer UtilitiesFree
Decimal degrees to DMS converter
degrees, minutes, seconds and hemisphere, free
A
POST /geo/decimal-to-dms$0.002⚙️ Developer UtilitiesFree
Length of a degree of latitude
WGS-84 ground distance, free
A
POST /geo/degree-length-latitude$0.002⚙️ Developer UtilitiesFree
Length of a degree of longitude
ground distance at any latitude (WGS84), free
A
POST /geo/degree-length-longitude$0.002⚙️ Developer UtilitiesFree
Destination point calculator
great-circle lat/lon from bearing and distance, free
A
POST /geo/destination-point$0.002⚙️ Developer UtilitiesFree
DMS to decimal degrees converter
hemisphere letter, free
P
POST /geo/dms-to-decimal$0.002⚙️ Developer UtilitiesFree
Equirectangular distance
fast lat/lon distance approximation, free
P
POST /geo/equirectangular-distance$0.002⚙️ Developer UtilitiesFree
Great-circle interpolation
intermediate lat/lon between two points, free
A
POST /geo/geodesic-interpolate$0.002⚙️ Developer UtilitiesFree
Geohash bounding box
lat/lon corners from geohash, free
A
POST /geo/geohash-bbox$0.002⚙️ Developer UtilitiesFree
Geohash neighbors finder
8 adjacent cells, free
P
POST /geo/geohash-neighbors$0.002⚙️ Developer UtilitiesFree
Web map scale calculator
zoom, latitude & DPI to 1:N, free
P
POST /geo/map-scale$0.002⚙️ Developer UtilitiesFree
Web Mercator meters per pixel
ground resolution from zoom and latitude, free
A
POST /geo/meters-per-pixel$0.002⚙️ Developer UtilitiesFree
Lat lon to MGRS
military grid reference from coordinates, free
A
POST /geo/mgrs-from-latlon$0.002⚙️ Developer UtilitiesFree
MGRS to lat/lon
military grid reference south-west corner to WGS84, free
A
POST /geo/mgrs-to-latlon$0.002⚙️ Developer UtilitiesFree
Point in polygon checker
test if a point lies inside a polygon, free
A
POST /geo/point-in-polygon$0.002⚙️ Developer UtilitiesFree
Polygon centroid calculator
area-weighted lat/lon center
A
POST /geo/polygon-centroid$0.002⚙️ Developer UtilitiesFree
Bing Maps quadkey decoder
tile X, Y and zoom from a quadkey string, free
A
POST /geo/quadkey-decode$0.002⚙️ Developer UtilitiesFree
Tile to Bing Maps quadkey
X/Y/zoom to quadkey string, free
A
POST /geo/quadkey-encode$0.002⚙️ Developer UtilitiesFree
Rhumb line bearing calculator
constant course between two points, free
P
POST /geo/rhumb-bearing$0.002⚙️ Developer UtilitiesFree
Rhumb line destination point
lat/lon from constant bearing and distance, free
A
POST /geo/rhumb-destination$0.002⚙️ Developer UtilitiesFree
Lat/lon to map tile
Web Mercator slippy X/Y from coordinates and zoom, free
A
POST /geo/tile-from-latlon$0.002⚙️ Developer UtilitiesFree
Lat lon to UTM converter
zone, easting, northing, free
P
POST /geo/utm-from-latlon$0.002⚙️ Developer UtilitiesFree
Vincenty distance calculator
WGS-84 ellipsoidal geodesic, free
A
POST /geo/vincenty-distance$0.002⚙️ Developer UtilitiesFree
Web Mercator unproject
meters to lat/lon (EPSG:3857), free
A
POST /geo/web-mercator-unproject$0.002⚙️ Developer UtilitiesFree
Arc length calculator
sector area from radius and central angle
P
POST /geom/arc-length$0.002⚙️ Developer UtilitiesFree
Barrel volume calculator
estimate cask volume from top radius, middle radius and height
P
POST /geom/barrel$0.002⚙️ Developer UtilitiesFree
Circle equation calculator
standard & general form, area, circumference
P
POST /geom/circle-equation$0.002⚙️ Developer UtilitiesFree
Circle–line intersection
find 0, 1 or 2 points from center, radius and line
A
POST /geom/circle-line-intersection$0.002⚙️ Developer UtilitiesFree
Cube calculator
volume, surface area and diagonals from edge, volume or area
A
POST /geom/cube$0.002⚙️ Developer UtilitiesFree
Cylinder volume calculator
lateral and total surface area from radius and height
P
POST /geom/cylinder$0.002⚙️ Developer UtilitiesFree
Distance between two points
Euclidean 2D calculator, free
A
POST /geom/distance-2d$0.002⚙️ Developer UtilitiesFree
Ellipsoid volume calculator
surface area by Knud Thomsen from three semi-axes
P
POST /geom/ellipsoid$0.002⚙️ Developer UtilitiesFree
Conical frustum calculator
volume, slant height and surface area from two radii and height
A
POST /geom/frustum-cone$0.002⚙️ Developer UtilitiesFree
Pyramid frustum calculator
volume from two base areas and height, free
A
POST /geom/frustum-pyramid$0.002⚙️ Developer UtilitiesFree
Hemisphere calculator
volume, curved and total surface area, free
A
POST /geom/hemisphere$0.002⚙️ Developer UtilitiesFree
Heron's formula calculator
triangle area from three side lengths
P
POST /geom/heron-area$0.002⚙️ Developer UtilitiesFree
Hexagonal pyramid calculator
volume and surface area from edge and height, free
A
POST /geom/hexagonal-pyramid$0.002⚙️ Developer UtilitiesFree
Hyperbola calculator
foci, vertices, eccentricity, asymptote slopes
P
POST /geom/hyperbola$0.002⚙️ Developer UtilitiesFree
Icosahedron calculator
volume and surface area from edge length, free
A
POST /geom/icosahedron$0.002⚙️ Developer UtilitiesFree
Line equation from two points
slope-intercept and standard form, free
A
POST /geom/line-equation$0.002⚙️ Developer UtilitiesFree
Midpoint calculator
center of a segment between two points
A
POST /geom/midpoint$0.002⚙️ Developer UtilitiesFree
Oblique prism volume
Cavalieri from base area and perpendicular height
A
POST /geom/oblique-prism$0.002⚙️ Developer UtilitiesFree
Octahedron calculator
volume, surface area, inradius and circumradius from edge
A
POST /geom/octahedron$0.002⚙️ Developer UtilitiesFree
Parabola calculator
vertex, focus, directrix and axis, free
A
POST /geom/parabola$0.002⚙️ Developer UtilitiesFree
Paraboloid volume calculator
volume of revolution from base radius and height
A
POST /geom/paraboloid$0.002⚙️ Developer UtilitiesFree
Parallel or perpendicular lines
slopes, relation and angle
A
POST /geom/parallel-perpendicular$0.002⚙️ Developer UtilitiesFree
Pentagonal prism calculator
volume and surface area from base edge and height
P
POST /geom/pentagonal-prism$0.002⚙️ Developer UtilitiesFree
Point to line distance
perpendicular distance to ax+by+c=0
P
POST /geom/point-line-distance$0.002⚙️ Developer UtilitiesFree
Polygon diagonals calculator
n(n−3)/2 for convex n-gons
A
POST /geom/polygon-diagonals$0.002⚙️ Developer UtilitiesFree
Polygon perimeter from coordinates
sum edge lengths, free
A
POST /geom/polygon-perimeter$0.002⚙️ Developer UtilitiesFree
Quadrilateral area calculator
shoelace formula from four vertices
P
POST /geom/quadrilateral-area$0.002⚙️ Developer UtilitiesFree
Rectangular prism calculator
volume, surface area, diagonal, free
A
POST /geom/rectangular-prism$0.002⚙️ Developer UtilitiesFree
Regular polygon calculator
area, perimeter, apothem, radius
A
POST /geom/regular-polygon$0.002⚙️ Developer UtilitiesFree
Right triangle calculator
missing side, angles and area
A
POST /geom/right-triangle$0.002⚙️ Developer UtilitiesFree
Section formula calculator
divide a segment in ratio m:n, free
A
POST /geom/section-formula$0.002⚙️ Developer UtilitiesFree
Circular sector area and perimeter
radius and angle, free
A
POST /geom/sector-area$0.002⚙️ Developer UtilitiesFree
Circular segment area
from radius and central angle
A
POST /geom/segment-area$0.002⚙️ Developer UtilitiesFree
Sphere volume calculator
volume and surface area from radius or diameter
A
POST /geom/sphere-volume$0.002⚙️ Developer UtilitiesFree
Spherical cap calculator
volume and curved surface area, free
A
POST /geom/spherical-cap$0.002⚙️ Developer UtilitiesFree
Spherical sector calculator
volume and surface area from radius and cap height
A
POST /geom/spherical-sector$0.002⚙️ Developer UtilitiesFree
Tank volume calculator
filled and total volume of horizontal or vertical cylindrical tanks
P
POST /geom/tank-volume$0.002⚙️ Developer UtilitiesFree
Tetrahedron volume calculator
surface area, height and insphere from edge length
P
POST /geom/tetrahedron$0.002⚙️ Developer UtilitiesFree
Trapezoid area calculator
bases, height, midsegment, free
A
POST /geom/trapezoid$0.002⚙️ Developer UtilitiesFree
30-60-90 triangle calculator
sides and area from any one side
P
POST /geom/triangle-30-60-90$0.002⚙️ Developer UtilitiesFree
AAS triangle calculator
two angles and a non-included side
A
POST /geom/triangle-aas$0.002⚙️ Developer UtilitiesFree
Triangle area from coordinates
shoelace formula, free
A
POST /geom/triangle-area-coordinates$0.002⚙️ Developer UtilitiesFree
ASA triangle calculator
two angles and included side, free
A
POST /geom/triangle-asa$0.002⚙️ Developer UtilitiesFree
Triangle centroid calculator
average of three vertices
A
POST /geom/triangle-centroid$0.002⚙️ Developer UtilitiesFree
Triangle orthocenter from coordinates
altitudes, free
A
POST /geom/triangle-orthocenter$0.002⚙️ Developer UtilitiesFree
SAS triangle calculator
third side, area, angles from two sides and included angle
P
POST /geom/triangle-sas$0.002⚙️ Developer UtilitiesFree
Triangular prism calculator
volume and surface area, free
A
POST /geom/triangular-prism$0.002⚙️ Developer UtilitiesFree
Two circles intersection
find intersection points from centers and radii, free
A
POST /geom/two-circles-intersection$0.002⚙️ Developer UtilitiesFree
Wedge volume calculator
rectangular wedge from base and two heights, free
A
POST /geom/wedge$0.002⚙️ Developer UtilitiesFree
Anion gap calculator
serum AG and albumin correction, free
A
POST /health/anion-gap$0.002⚙️ Developer UtilitiesFree
Blood pressure category calculator
ACC/AHA stages, free
A
POST /health/blood-pressure-category$0.002⚙️ Developer UtilitiesFree
BMI Prime calculator
ratio to the 25 upper-normal threshold, free
A
POST /health/bmi-prime$0.002⚙️ Developer UtilitiesFree
Harris-Benedict BMR calculator
basal metabolic rate from weight, height, age, sex
A
POST /health/bmr-harris-benedict$0.002⚙️ Developer UtilitiesFree
Katch-McArdle BMR calculator
BMR from lean mass, free
A
POST /health/bmr-katch-mcardle$0.002⚙️ Developer UtilitiesFree
Total body water calculator
Watson TBW volume and percentage, free
A
POST /health/body-water-percentage$0.002⚙️ Developer UtilitiesFree
Body surface area Du Bois calculator
BSA from height and weight, free
A
POST /health/bsa-dubois$0.002⚙️ Developer UtilitiesFree
Body surface area calculator
Mosteller formula BSA, free
P
POST /health/bsa-mosteller$0.002⚙️ Developer UtilitiesFree
Calories burned calculator
MET, weight and duration, free estimate
A
POST /health/calories-burned$0.002⚙️ Developer UtilitiesFree
Child and teen BMI calculator
BMI percentile and band, free
A
POST /health/child-bmi$0.002⚙️ Developer UtilitiesFree
Corrected calcium calculator
albumin-adjusted serum calcium, free
A
POST /health/corrected-calcium$0.002⚙️ Developer UtilitiesFree
Cycling calorie calculator
calories burned biking, free
A
POST /health/cycling-calories$0.002⚙️ Developer UtilitiesFree
Fat-free mass index calculator
FFMI from weight, height and body fat, free
A
POST /health/fat-free-mass-index$0.002⚙️ Developer UtilitiesFree
Daily fiber intake calculator
recommended grams from calories, free
A
POST /health/fiber-intake$0.002⚙️ Developer UtilitiesFree
Mean arterial pressure calculator
MAP from systolic and diastolic, free
A
POST /health/mean-arterial-pressure$0.002⚙️ Developer UtilitiesFree
Pack years calculator
cigarettes and years smoked, free
P
POST /health/pack-years$0.002⚙️ Developer UtilitiesFree
Pregnancy weight gain calculator
BMI and weeks range, free
P
POST /health/pregnancy-weight-gain$0.002⚙️ Developer UtilitiesFree
Daily protein intake calculator
grams from weight and g/kg target, free
A
POST /health/protein-intake$0.002⚙️ Developer UtilitiesFree
Riegel race time predictor
predict finish times from a known race
A
POST /health/race-time-predictor$0.002⚙️ Developer UtilitiesFree
Running calorie calculator
calories burned from distance, weight & grade
P
POST /health/running-calories$0.002⚙️ Developer UtilitiesFree
Running pace calculator
min/km and min/mile from distance & time
P
POST /health/running-pace$0.002⚙️ Developer UtilitiesFree
Steps to distance calculator
convert steps to km, miles, free
A
POST /health/steps-to-distance$0.002⚙️ Developer UtilitiesFree
Swimming pace calculator
pace per 100m and 100 yards from distance & time
P
POST /health/swim-pace$0.002⚙️ Developer UtilitiesFree
Target heart rate Karvonen calculator
reserve method, free
A
POST /health/target-hr-karvonen$0.002⚙️ Developer UtilitiesFree
VO2 max Cooper test calculator
12-min distance estimate, free
A
POST /health/vo2max-cooper$0.002⚙️ Developer UtilitiesFree
Waist-to-height ratio calculator
WHtR and risk category, free
A
POST /health/waist-height-ratio$0.002⚙️ Developer UtilitiesFree
Waist-to-hip ratio calculator
WHR and health-risk band, free
P
POST /health/waist-hip-ratio$0.002⚙️ Developer UtilitiesFree
BPM to milliseconds calculator
note durations & delay times, free
P
POST /hobby/bpm-to-ms$0.002⚙️ Developer UtilitiesFree
Cents between frequencies calculator
musical interval in cents, free
P
POST /hobby/cents-interval$0.002⚙️ Developer UtilitiesFree
Chord note calculator
notes and intervals from root and quality
A
POST /hobby/chord-notes$0.002⚙️ Developer UtilitiesFree
Crop factor calculator
full-frame equivalent focal length & aperture, free
A
POST /hobby/crop-factor$0.002⚙️ Developer UtilitiesFree
Depth of field calculator
near, far & total DOF, free
P
POST /hobby/depth-of-field$0.002⚙️ Developer UtilitiesFree
Equivalent exposure calculator
match aperture, shutter & ISO, free
A
POST /hobby/equivalent-exposure$0.002⚙️ Developer UtilitiesFree
Exposure value calculator
EV from aperture, shutter, ISO
A
POST /hobby/exposure-value$0.002⚙️ Developer UtilitiesFree
Camera field of view calculator
AOV from focal length & sensor
A
POST /hobby/field-of-view$0.002⚙️ Developer UtilitiesFree
Golden ratio font size calculator
heading & body type scale, free
A
POST /hobby/golden-ratio-type$0.002⚙️ Developer UtilitiesFree
Knitting gauge calculator
cast on stitches & rows, free
P
POST /hobby/knitting-gauge$0.002⚙️ Developer UtilitiesFree
Modular type scale generator
base, ratio & steps, free
P
POST /hobby/modular-scale$0.002⚙️ Developer UtilitiesFree
Musical interval calculator
semitones and interval name from two notes, free
A
POST /hobby/musical-interval$0.002⚙️ Developer UtilitiesFree
Note frequency calculator
equal temperament Hz from A4
A
POST /hobby/note-frequency$0.002⚙️ Developer UtilitiesFree
NPF rule calculator
sharper max shutter for stars, free
P
POST /hobby/npf-rule$0.002⚙️ Developer UtilitiesFree
Poker outs and odds calculator
next card and river hit probability, free
A
POST /hobby/poker-odds$0.002⚙️ Developer UtilitiesFree
Print size & DPI calculator
pixels to inches, free
A
POST /hobby/print-dpi$0.002⚙️ Developer UtilitiesFree
Reading time estimator
word count and WPM to duration, free
A
POST /hobby/reading-time$0.002⚙️ Developer UtilitiesFree
Epoxy resin mix calculator
resin & hardener amounts by ratio, free
A
POST /hobby/resin-mix$0.002⚙️ Developer UtilitiesFree
Musical scale generator
notes from root and scale type, free
A
POST /hobby/scale-notes$0.002⚙️ Developer UtilitiesFree
Music transposition calculator
notes and chords by semitones
A
POST /hobby/transpose$0.002⚙️ Developer UtilitiesFree
Yarn weight substitution calculator
skeins to buy from yardage, free
A
POST /hobby/yarn-substitution$0.002⚙️ Developer UtilitiesFree
Air conditioner BTU calculator
room cooling capacity, free
P
POST /home/ac-btu$0.002⚙️ Developer UtilitiesFree
Concrete block calculator
blocks from wall area, face size and waste
A
POST /home/blocks$0.002⚙️ Developer UtilitiesFree
Carpet calculator
linear metres and area from room size and roll width free
A
POST /home/carpet$0.002⚙️ Developer UtilitiesFree
Concrete column calculator
cylindrical volume from diameter, height and count
A
POST /home/concrete-column$0.002⚙️ Developer UtilitiesFree
Concrete footing calculator
volume from L×W×D×count, free
P
POST /home/concrete-footing$0.002⚙️ Developer UtilitiesFree
Concrete slab calculator
volume and bags from length, width, thickness free
A
POST /home/concrete-slab$0.002⚙️ Developer UtilitiesFree
Crown molding calculator
sticks from perimeter and waste, free
P
POST /home/crown-molding$0.002⚙️ Developer UtilitiesFree
Deck board calculator
boards needed from area, size, gap and waste free
A
POST /home/deck-boards$0.002⚙️ Developer UtilitiesFree
Fence post calculator
posts and rails from length and spacing, free
P
POST /home/fence-posts$0.002⚙️ Developer UtilitiesFree
Lawn fertilizer calculator
pounds to apply from area, N rate, and bag nitrogen % free
A
POST /home/fertilizer$0.002⚙️ Developer UtilitiesFree
Floor tile calculator
tiles and boxes from room area, size and waste free
A
POST /home/floor-tiles$0.002⚙️ Developer UtilitiesFree
Gravel calculator
volume and weight from area, depth and density, free
P
POST /home/gravel$0.002⚙️ Developer UtilitiesFree
Heater BTU calculator
room volume, insulation and temperature rise free
A
POST /home/heater-btu$0.002⚙️ Developer UtilitiesFree
Insulation R-value calculator
total assembly R and U-factor from layers
A
POST /home/insulation$0.002⚙️ Developer UtilitiesFree
Laminate flooring calculator
packs from room area, coverage and waste
A
POST /home/laminate-flooring$0.002⚙️ Developer UtilitiesFree
Mortar calculator
volume and bags from brick or block count free
A
POST /home/mortar$0.002⚙️ Developer UtilitiesFree
Paver calculator
patio pavers needed from area, size and waste free
A
POST /home/pavers$0.002⚙️ Developer UtilitiesFree
Pool chlorine dosage calculator
dose from volume, free chlorine levels, and product strength free
A
POST /home/pool-chlorine$0.002⚙️ Developer UtilitiesFree
Swimming pool volume calculator
liters and gallons from shape and dimensions
A
POST /home/pool-volume$0.002⚙️ Developer UtilitiesFree
Roof pitch calculator
rise, run, slope angle and rafter factor, free
P
POST /home/roof-pitch$0.002⚙️ Developer UtilitiesFree
Roofing shingles calculator
bundles and squares from area and pitch free
A
POST /home/roof-shingles$0.002⚙️ Developer UtilitiesFree
Sand calculator
volume and weight from area, depth and density
A
POST /home/sand$0.002⚙️ Developer UtilitiesFree
Staircase step calculator
riser count, exact riser and tread run
A
POST /home/staircase-steps$0.002⚙️ Developer UtilitiesFree
Topsoil calculator
volume in cubic yards and cubic meters from area and depth free
A
POST /home/topsoil$0.002⚙️ Developer UtilitiesFree
Wall stud calculator
count studs from length, spacing and openings
A
POST /home/wall-studs$0.002⚙️ Developer UtilitiesFree
Wall tile calculator
tiles and boxes from area, size and waste
A
POST /home/wall-tiles$0.002⚙️ Developer UtilitiesFree
Wallpaper rolls calculator
pattern repeat included, free
P
POST /home/wallpaper-rolls$0.002⚙️ Developer UtilitiesFree
Water tank volume calculator
capacity in liters and gallons at a fill depth, free
P
POST /home/water-tank-volume$0.002⚙️ Developer UtilitiesFree
Buy one get one discount calculator
BOGO effective % free
A
POST /life/bogo-discount$0.002⚙️ Developer UtilitiesFree
Recipe cost per serving calculator
ingredient costs ÷ servings, free
P
POST /life/cost-per-serving$0.002⚙️ Developer UtilitiesFree
Shared expense splitter
itemized costs by weight free
A
POST /life/expense-split$0.002⚙️ Developer UtilitiesFree
Quit a habit savings calculator
money saved by quitting free
A
POST /life/habit-savings$0.002⚙️ Developer UtilitiesFree
Markup to margin converter
selling price, free
A
POST /life/markup-margin$0.002⚙️ Developer UtilitiesFree
Overtime pay calculator
hourly rate, OT hours, gross pay, free
A
POST /life/overtime-pay$0.002⚙️ Developer UtilitiesFree
Price per 100g calculator
compare products, find cheapest, free
A
POST /life/price-per-100g$0.002⚙️ Developer UtilitiesFree
Rule of 114 and 144 calculator
years to triple or quadruple free
A
POST /life/rule-of-114$0.002⚙️ Developer UtilitiesFree
Salary to hourly converter
annual pay to hourly wage free
A
POST /life/salary-to-hourly$0.002⚙️ Developer UtilitiesFree
Sales tax calculator
tax amount and total from rate, free
P
POST /life/sales-tax$0.002⚙️ Developer UtilitiesFree
Savings goal time calculator
months to target with fixed deposits
P
POST /life/savings-goal-time$0.002⚙️ Developer UtilitiesFree
Subscription annual cost calculator
monthly & yearly totals, free
A
POST /life/subscription-annual$0.002⚙️ Developer UtilitiesFree
Tip and split calculator
bill, tip %, per person, free
A
POST /life/tip-split$0.002⚙️ Developer UtilitiesFree
Unit price comparison calculator
price per unit and best value, free
P
POST /life/unit-price$0.002⚙️ Developer UtilitiesFree
Arithmetic sequence calculator
nth term and partial sum, free
A
POST /math/arithmetic-sequence$0.002⚙️ Developer UtilitiesFree
Arithmetic series sum calculator
S = n(a1+an)/2, free
P
POST /math/arithmetic-series-sum$0.002⚙️ Developer UtilitiesFree
Catalan number calculator
nth Catalan C(n), free
A
POST /math/catalan-number$0.002⚙️ Developer UtilitiesFree
Double factorial calculator
compute n!! with BigInt precision
A
POST /math/double-factorial$0.002⚙️ Developer UtilitiesFree
Factorial calculator
n! exact BigInt product, free
A
POST /math/factorial-calculator$0.002⚙️ Developer UtilitiesFree
Fibonacci number calculator
nth term and sequence, free
A
POST /math/fibonacci$0.002⚙️ Developer UtilitiesFree
Sum of Fibonacci series
first n terms equal F(n+2)−1
A
POST /math/fibonacci-sum$0.002⚙️ Developer UtilitiesFree
Infinite geometric series sum
S = a/(1−r), free calculator
A
POST /math/geometric-series-sum$0.002⚙️ Developer UtilitiesFree
Hexagonal number calculator
H(n)=n(2n−1) and membership test, free
A
POST /math/hexagonal-number$0.002⚙️ Developer UtilitiesFree
Look-and-say sequence
n-th term from a seed by run-length
A
POST /math/look-and-say$0.002⚙️ Developer UtilitiesFree
Padovan sequence calculator
n-th Padovan number P(n)
P
POST /math/padovan-number$0.002⚙️ Developer UtilitiesFree
Pentagonal number calculator
P(n)=n(3n−1)/2 and membership test
A
POST /math/pentagonal-number$0.002⚙️ Developer UtilitiesFree
Polygonal number calculator
n-th s-gonal figurate number
P
POST /math/polygonal-number$0.002⚙️ Developer UtilitiesFree
Primorial calculator
n# product of primes ≤ n, free
A
POST /math/primorial$0.002⚙️ Developer UtilitiesFree
Square pyramidal number
sum of first n squares n(n+1)(2n+1)/6
A
POST /math/pyramidal-number$0.002⚙️ Developer UtilitiesFree
Stern diatomic / Stern-Brocot sequence
n-th term s(n)
P
POST /math/stern-brocot$0.002⚙️ Developer UtilitiesFree
Sum of first n even numbers
2+4+…+2n = n(n+1)
A
POST /math/sum-of-even$0.002⚙️ Developer UtilitiesFree
Sum of first n odd numbers
equals n squared, free calculator
A
POST /math/sum-of-odd$0.002⚙️ Developer UtilitiesFree
Sum of first n squares
1²+2²+…+n² = n(n+1)(2n+1)/6
A
POST /math/sum-of-squares$0.002⚙️ Developer UtilitiesFree
Sylvester sequence calculator
nth term with BigInt, free
A
POST /math/sylvester-sequence$0.002⚙️ Developer UtilitiesFree
Angular velocity calculator
ω from angle & time or RPM, free
P
POST /mech/angular-velocity$0.002⚙️ Developer UtilitiesFree
Atwood machine calculator
acceleration & tension, free in browser
P
POST /mech/atwood-machine$0.002⚙️ Developer UtilitiesFree
Average velocity calculator
displacement over time in m/s and km/h free
A
POST /mech/average-velocity$0.002⚙️ Developer UtilitiesFree
Banked curve calculator
ideal banking angle from radius and speed
A
POST /mech/banked-curve$0.002⚙️ Developer UtilitiesFree
Centripetal acceleration calculator
a = v²/r from speed and radius free
A
POST /mech/centripetal-acceleration$0.002⚙️ Developer UtilitiesFree
Centripetal force calculator
F=mv²/r from mass, speed, and radius
A
POST /mech/centripetal-force$0.002⚙️ Developer UtilitiesFree
Coefficient of friction calculator
μ = Ff / N, free in browser
P
POST /mech/coefficient-of-friction$0.002⚙️ Developer UtilitiesFree
Elastic collision calculator
final velocities of two masses in 1D free
A
POST /mech/elastic-collision$0.002⚙️ Developer UtilitiesFree
Force calculator
F=ma from mass and acceleration (or solve mass/accel)
A
POST /mech/force-mass-accel$0.002⚙️ Developer UtilitiesFree
Free fall calculator
fall time and impact velocity from rest
A
POST /mech/free-fall$0.002⚙️ Developer UtilitiesFree
Hooke's law calculator
spring force F=kx (or solve k or x)
A
POST /mech/hookes-law$0.002⚙️ Developer UtilitiesFree
Horizontal projectile motion calculator
fall time, range and impact velocity free
A
POST /mech/horizontal-projectile$0.002⚙️ Developer UtilitiesFree
Impulse calculator
impulse and Δp from force and contact time
A
POST /mech/impulse$0.002⚙️ Developer UtilitiesFree
Inclined plane calculator
acceleration and normal force free
A
POST /mech/inclined-plane$0.002⚙️ Developer UtilitiesFree
Kinematics distance calculator
displacement from velocity, acceleration, time
A
POST /mech/kinematics-distance$0.002⚙️ Developer UtilitiesFree
Final velocity calculator
v = u + at, free in browser
P
POST /mech/kinematics-velocity$0.002⚙️ Developer UtilitiesFree
Kinetic energy calculator
KE = ½mv², free in browser
P
POST /mech/kinetic-energy$0.002⚙️ Developer UtilitiesFree
Moment of inertia calculator
ring, disc, sphere, rod, free
P
POST /mech/moment-of-inertia$0.002⚙️ Developer UtilitiesFree
Momentum calculator
linear momentum p=mv in kg·m/s free
A
POST /mech/momentum$0.002⚙️ Developer UtilitiesFree
Newton's second law calculator
F = ma, free in browser
P
POST /mech/newton-second-law$0.002⚙️ Developer UtilitiesFree
Pendulum length calculator
required length from period and g free
A
POST /mech/pendulum-length$0.002⚙️ Developer UtilitiesFree
Power calculator
mechanical power in watts and horsepower from work and time
A
POST /mech/power$0.002⚙️ Developer UtilitiesFree
Power from force and velocity
P=Fv in watts free
A
POST /mech/power-force-velocity$0.002⚙️ Developer UtilitiesFree
Projectile from height calculator
range and flight time above ground
A
POST /mech/projectile-launch-from-height$0.002⚙️ Developer UtilitiesFree
Pulley mechanical advantage calculator
ideal IMA and effort force free
A
POST /mech/pulley-mechanical-advantage$0.002⚙️ Developer UtilitiesFree
Rotational kinetic energy calculator
KE=½Iω² in joules free
A
POST /mech/rotational-kinetic-energy$0.002⚙️ Developer UtilitiesFree
Spring constant calculator
k = F/x, free in browser
P
POST /mech/spring-constant$0.002⚙️ Developer UtilitiesFree
Terminal velocity calculator
mass, drag, density and area free
A
POST /mech/terminal-velocity$0.002⚙️ Developer UtilitiesFree
Torque calculator
τ = rF sin(θ) in newton-metres
A
POST /mech/torque$0.002⚙️ Developer UtilitiesFree
Work done calculator
W=Fd cos θ in joules free
A
POST /mech/work-done$0.002⚙️ Developer UtilitiesFree
Aliquot sum calculator
proper divisors, perfect / deficient / abundant
P
POST /numth/aliquot-sum$0.002⚙️ Developer UtilitiesFree
Amicable numbers checker
test if two integers form an amicable pair
A
POST /numth/amicable-numbers$0.002⚙️ Developer UtilitiesFree
Armstrong number checker
narcissistic numbers, digit power sum
P
POST /numth/armstrong-number$0.002⚙️ Developer UtilitiesFree
Automorphic number checker
does n² end with n, free
A
POST /numth/automorphic-number$0.002⚙️ Developer UtilitiesFree
Digit sum calculator
sum digits in any base, free
A
POST /numth/digit-sum$0.002⚙️ Developer UtilitiesFree
Digital root calculator
repeated digit sum and additive persistence
A
POST /numth/digital-root$0.002⚙️ Developer UtilitiesFree
Number of divisors calculator
tau(n) from prime factors
A
POST /numth/divisor-count$0.002⚙️ Developer UtilitiesFree
Sum of divisors calculator
sigma(n) from prime factors
P
POST /numth/divisor-sum$0.002⚙️ Developer UtilitiesFree
Euler's totient φ(n)
count coprimes from prime factors
A
POST /numth/euler-totient$0.002⚙️ Developer UtilitiesFree
Extended Euclidean calculator
gcd and Bézout coefficients x, y
A
POST /numth/extended-euclidean$0.002⚙️ Developer UtilitiesFree
Factorial prime factorization
n! factors via Legendre formula
P
POST /numth/factorial-prime-factors$0.002⚙️ Developer UtilitiesFree
Happy number checker
sum of squares of digits until 1 or a cycle
A
POST /numth/happy-number$0.002⚙️ Developer UtilitiesFree
Jacobi symbol calculator
(a/n) via quadratic reciprocity
P
POST /numth/jacobi-symbol$0.002⚙️ Developer UtilitiesFree
Legendre symbol (a/p)
quadratic residuosity mod odd prime
A
POST /numth/legendre-symbol$0.002⚙️ Developer UtilitiesFree
Mersenne number checker
compute 2^p−1 and Lucas-Lehmer primality
A
POST /numth/mersenne-number$0.002⚙️ Developer UtilitiesFree
Modular exponentiation calculator
base^exp mod m (fast BigInt)
P
POST /numth/modular-exponentiation$0.002⚙️ Developer UtilitiesFree
Modular multiplicative inverse
a⁻¹ mod m via extended Euclidean
A
POST /numth/modular-inverse$0.002⚙️ Developer UtilitiesFree
Next prime after n
smallest prime strictly greater than n
A
POST /numth/next-prime$0.002⚙️ Developer UtilitiesFree
Pandigital number checker
each base digit once, missing digits
P
POST /numth/pandigital-checker$0.002⚙️ Developer UtilitiesFree
Previous prime finder
largest prime strictly less than n
P
POST /numth/prev-prime$0.002⚙️ Developer UtilitiesFree
Prime counting function π(n)
count primes ≤ n by sieve
A
POST /numth/prime-counting$0.002⚙️ Developer UtilitiesFree
Quadratic residue checker
is a a square mod m, list residues
A
POST /numth/quadratic-residue$0.002⚙️ Developer UtilitiesFree
Radix converter
change integer bases 2–36, free
A
POST /numth/radix-convert$0.002⚙️ Developer UtilitiesFree
Factorial trailing zeros
count zeros of n! via powers of five
A
POST /numth/trailing-zeros-factorial$0.002⚙️ Developer UtilitiesFree
Twin prime checker
test (n, n+2) and list pairs up to a limit
A
POST /numth/twin-primes$0.002⚙️ Developer UtilitiesFree
Brewster angle calculator
polarization angle from n₁, n₂, free
P
POST /optics/brewster-angle$0.002⚙️ Developer UtilitiesFree
Critical angle calculator
total internal reflection from two indices
A
POST /optics/critical-angle$0.002⚙️ Developer UtilitiesFree
Diffraction grating calculator
angle from d, λ, order m, free
P
POST /optics/diffraction-grating$0.002⚙️ Developer UtilitiesFree
F-stop calculator
f-number from focal length and aperture diameter, free
A
POST /optics/f-number$0.002⚙️ Developer UtilitiesFree
Lens magnification calculator
linear m = −v/u for lenses and mirrors, free
A
POST /optics/lens-magnification$0.002⚙️ Developer UtilitiesFree
Lens power calculator
diopters from focal length (m), free
P
POST /optics/lens-power$0.002⚙️ Developer UtilitiesFree
Mirror equation calculator
image distance & magnification from f and do
A
POST /optics/mirror-equation$0.002⚙️ Developer UtilitiesFree
Single-slit diffraction calculator
angular position of minima from a, λ and order m, free
A
POST /optics/single-slit-diffraction$0.002⚙️ Developer UtilitiesFree
Snell's law calculator
refraction angle from n1, n2 and incidence, free
A
POST /optics/snell-law$0.002⚙️ Developer UtilitiesFree
Telescope magnification calculator
angular M from objective & eyepiece
A
POST /optics/telescope-magnification$0.002⚙️ Developer UtilitiesFree
Beat frequency calculator
f_beat = |f1 − f2| free, rejects negative Hz
A
POST /phys/beat-frequency$0.002⚙️ Developer UtilitiesFree
Doppler effect calculator
observed frequency and frequency shift, free
P
POST /phys/doppler-effect$0.002⚙️ Developer UtilitiesFree
Doppler shift sound calculator
perceived frequency from relative speed
A
POST /phys/doppler-sound$0.002⚙️ Developer UtilitiesFree
Period to frequency calculator
convert T↔f (Hz) free, rejects zero
A
POST /phys/period-frequency$0.002⚙️ Developer UtilitiesFree
Pipe resonance calculator
open/closed pipe fundamental and harmonics
A
POST /phys/pipe-resonance$0.002⚙️ Developer UtilitiesFree
Sound intensity calculator
I = P / (4πr²) in W/m², free
P
POST /phys/sound-intensity$0.002⚙️ Developer UtilitiesFree
Decibel calculator
sound intensity level L=10·log₁₀(I/I₀) free, rejects non-positive I
A
POST /phys/sound-intensity-db$0.002⚙️ Developer UtilitiesFree
Speed of sound calculator
dry air from temperature (m/s)
A
POST /phys/speed-of-sound-air$0.002⚙️ Developer UtilitiesFree
Standing wave calculator
nodes and wavelength from harmonic number and string length, free
A
POST /phys/standing-wave$0.002⚙️ Developer UtilitiesFree
Wave speed on a string calculator
v = √(T/μ), free
P
POST /phys/wave-on-string-speed$0.002⚙️ Developer UtilitiesFree
Wave speed calculator
v=fλ from frequency and wavelength (or solve any)
A
POST /phys/wave-speed$0.002⚙️ Developer UtilitiesFree
Birthday paradox calculator
shared day probability for n people
A
POST /prob/birthday-paradox$0.002⚙️ Developer UtilitiesFree
Coin flip probability
exactly k heads in n flips, free
A
POST /prob/coin-flip$0.002⚙️ Developer UtilitiesFree
Conditional probability calculator
P(A|B) and independence test
P
POST /prob/conditional-probability$0.002⚙️ Developer UtilitiesFree
Dice sum probability
every total for k dice with s sides
A
POST /prob/dice-sum$0.002⚙️ Developer UtilitiesFree
Dice roll probability
exact or at-least target sum with k s-sided dice
P
POST /prob/dice-target$0.002⚙️ Developer UtilitiesFree
Expected value calculator
mean, variance and standard deviation
A
POST /prob/expected-value$0.002⚙️ Developer UtilitiesFree
Geometric distribution calculator
P(first success on trial k) and E[X]
P
POST /prob/geometric-distribution$0.002⚙️ Developer UtilitiesFree
Hypergeometric probability
k successes in n draws, free
A
POST /prob/hypergeometric$0.002⚙️ Developer UtilitiesFree
Odds to probability converter
a to b, percent, free
A
POST /prob/odds-converter$0.002⚙️ Developer UtilitiesFree
Poisson probability calculator
P(X=k), CDF, mean and variance
A
POST /prob/poisson-distribution$0.002⚙️ Developer UtilitiesFree
Poker hand odds
exact pair, flush, full house probability
A
POST /prob/poker-odds$0.002⚙️ Developer UtilitiesFree
Beam deflection calculator
simply supported max δ = PL³/(48EI)
A
POST /sci/beam-deflection$0.002⚙️ Developer UtilitiesFree
Bending stress calculator
σ = My/I elastic flexure formula
A
POST /sci/bending-stress$0.002⚙️ Developer UtilitiesFree
Gear ratio calculator
teeth counts to GR and output speed, free
P
POST /sci/gear-ratio$0.002⚙️ Developer UtilitiesFree
Shear stress calculator
τ = F/A in pascals, free
P
POST /sci/shear-stress$0.002⚙️ Developer UtilitiesFree
Stress calculator
mechanical stress σ = F/A in pascals and megapascals, free
A
POST /sci/stress$0.002⚙️ Developer UtilitiesFree
Thermal stress calculator
constrained bar σ = E·α·ΔT in Pa and MPa, free
A
POST /sci/thermal-stress$0.002⚙️ Developer UtilitiesFree
Young's modulus calculator
elasticity E = σ/ε, solve stress, strain or E, free
A
POST /sci/youngs-modulus$0.002⚙️ Developer UtilitiesFree
Coefficient of variation calculator
CV ratio and percentage from a list
A
POST /stat/coefficient-variation$0.002⚙️ Developer UtilitiesFree
Five-number summary calculator
min, Q1, median, Q3, max of a data set, free
A
POST /stat/five-number-summary$0.002⚙️ Developer UtilitiesFree
Geometric mean calculator
n-th root of the product of positive numbers, free
A
POST /stat/geometric-mean$0.002⚙️ Developer UtilitiesFree
Harmonic mean calculator
reciprocal average of positive numbers
P
POST /stat/harmonic-mean$0.002⚙️ Developer UtilitiesFree
Linear regression calculator
least-squares slope, intercept and R², free
A
POST /stat/linear-regression$0.002⚙️ Developer UtilitiesFree
Mean median mode calculator
average, mid value, most common, range
P
POST /stat/mean-median-mode$0.002⚙️ Developer UtilitiesFree
Quartile and IQR calculator
Q1 Q2 Q3, range and outlier fences
P
POST /stat/quartiles$0.002⚙️ Developer UtilitiesFree
Skewness and kurtosis calculator
sample shape of a data set
P
POST /stat/skewness-kurtosis$0.002⚙️ Developer UtilitiesFree
Variance calculator
population and sample variance with mean
A
POST /stat/variance$0.002⚙️ Developer UtilitiesFree
Weighted average calculator
mean of values with weights
A
POST /stat/weighted-mean$0.002⚙️ Developer UtilitiesFree
Z-score calculator
standardize values with mean and standard deviation, free
A
POST /stat/z-score$0.002⚙️ Developer UtilitiesFree
Remove duplicate lines
keep first occurrences, free online
A
POST /str/dedupe-lines$0.002⚙️ Developer UtilitiesFree
Convert to dot.case
turn any phrase into dot.case, free
A
POST /str/dot-case$0.002⚙️ Developer UtilitiesFree
List unique words
extract word list in order, free
A
POST /str/extract-unique-words$0.002⚙️ Developer UtilitiesFree
Find and replace text
swap every match, free online
A
POST /str/find-replace$0.002⚙️ Developer UtilitiesFree
Kebab-case converter
lowercase words joined with hyphens, free
P
POST /str/kebab-case$0.002⚙️ Developer UtilitiesFree
Count lines
total, non-empty and blank, free
A
POST /str/line-count$0.002⚙️ Developer UtilitiesFree
Convert to lowercase
turn any text into lower case letters, free
A
POST /str/lowercase$0.002⚙️ Developer UtilitiesFree
Add line numbers to text
sequential numbering, free online
P
POST /str/number-lines$0.002⚙️ Developer UtilitiesFree
Pad text
fill a string to a target width left, right, or both sides, free
A
POST /str/pad$0.002⚙️ Developer UtilitiesFree
Count paragraphs
blank-line paragraph counter, free
P
POST /str/paragraph-count$0.002⚙️ Developer UtilitiesFree
PascalCase converter
convert text to PascalCase, free
A
POST /str/pascal-case$0.002⚙️ Developer UtilitiesFree
Remove accents from text
strip diacritics to plain ASCII letters, free
A
POST /str/remove-accents$0.002⚙️ Developer UtilitiesFree
Remove line breaks from text
join to a single line (optional space), free
A
POST /str/remove-line-breaks$0.002⚙️ Developer UtilitiesFree
Remove extra spaces
collapse repeated spaces and trim, free
A
POST /str/remove-spaces$0.002⚙️ Developer UtilitiesFree
Reverse text
flip character order, Unicode-safe, free
A
POST /str/reverse$0.002⚙️ Developer UtilitiesFree
Reverse word order
flip words, keep each word intact, free
P
POST /str/reverse-words$0.002⚙️ Developer UtilitiesFree
Sentence case converter
capitalize sentences, free
A
POST /str/sentence-case$0.002⚙️ Developer UtilitiesFree
Sentence counter
count sentences in text free
A
POST /str/sentence-count$0.002⚙️ Developer UtilitiesFree
Convert to snake_case
turn any phrase into snake_case, free
A
POST /str/snake-case$0.002⚙️ Developer UtilitiesFree
Sort lines alphabetically
A–Z or Z–A, free online
A
POST /str/sort-lines$0.002⚙️ Developer UtilitiesFree
Title case converter
capitalize words with small-word rules, free
P
POST /str/title-case$0.002⚙️ Developer UtilitiesFree
Trim whitespace from every line
strip leading and trailing spaces, free
P
POST /str/trim-lines$0.002⚙️ Developer UtilitiesFree
Truncate text
max length with ellipsis, optional word boundary, free
P
POST /str/truncate$0.002⚙️ Developer UtilitiesFree
Word & character counter
count words, sentences, paragraphs free
A
POST /str/word-count$0.002⚙️ Developer UtilitiesFree
Area thermal expansion calculator
ΔA = A₀·α·ΔT free
A
POST /thermo/area-expansion$0.002⚙️ Developer UtilitiesFree
Bernoulli equation calculator
unknown pressure from density, speed, height, free
P
POST /thermo/bernoulli-pressure$0.002⚙️ Developer UtilitiesFree
Boyle's law calculator
find final P or V from P1·V1=P2·V2 at constant T, free
A
POST /thermo/boyles-law$0.002⚙️ Developer UtilitiesFree
Buoyancy calculator
F_b = ρ V g (Archimedes), free
P
POST /thermo/buoyant-force$0.002⚙️ Developer UtilitiesFree
Celsius to Fahrenheit calculator
convert C↔F free online
A
POST /thermo/celsius-fahrenheit$0.002⚙️ Developer UtilitiesFree
Pipe flow continuity calculator
outlet speed from A1·v1=A2·v2, free
A
POST /thermo/continuity-equation$0.002⚙️ Developer UtilitiesFree
Partial pressure calculator
Dalton's law Pi=yi·P, free
A
POST /thermo/dalton-partial-pressure$0.002⚙️ Developer UtilitiesFree
Entropy change calculator
ΔS = Q/T from heat transferred and absolute temperature, free
A
POST /thermo/entropy-change$0.002⚙️ Developer UtilitiesFree
Mixing temperature calculator
equilibrium after mixing two masses, free
P
POST /thermo/final-temperature-mixing$0.002⚙️ Developer UtilitiesFree
Gas density calculator
ideal gas ρ = PM/RT from pressure, molar mass and T, free
A
POST /thermo/gas-density$0.002⚙️ Developer UtilitiesFree
Molar volume calculator
ideal gas Vm = RT/P from pressure and temperature, free
A
POST /thermo/gas-molar-volume$0.002⚙️ Developer UtilitiesFree
Gay-Lussac law calculator
P/T at constant volume, free
A
POST /thermo/gay-lussac-law$0.002⚙️ Developer UtilitiesFree
Specific heat calculator
heat energy Q=mcΔT in joules
A
POST /thermo/heat-energy$0.002⚙️ Developer UtilitiesFree
Hydrostatic pressure calculator
P = ρ·g·h with optional atmospheric offset, free
A
POST /thermo/hydrostatic-pressure$0.002⚙️ Developer UtilitiesFree
Ideal gas law calculator
solve PV = nRT for P, V, n, or T, free
P
POST /thermo/ideal-gas-law$0.002⚙️ Developer UtilitiesFree
Isothermal work calculator
ideal-gas W=nRT ln(V2/V1), free
A
POST /thermo/isothermal-work$0.002⚙️ Developer UtilitiesFree
Kelvin converter
Celsius, Fahrenheit and Kelvin together, free
A
POST /thermo/kelvin-converter$0.002⚙️ Developer UtilitiesFree
Linear thermal expansion calculator
ΔL = L₀·α·ΔT from length, coefficient and temperature change, free
A
POST /thermo/linear-expansion$0.002⚙️ Developer UtilitiesFree
Newton's law of cooling calculator
T(t) from Ta, T0, k, t, free
P
POST /thermo/newton-cooling$0.002⚙️ Developer UtilitiesFree
Pressure calculator
P=F/A in Pa, bar and psi, free
A
POST /thermo/pressure-force-area$0.002⚙️ Developer UtilitiesFree
Relative humidity calculator
RH from actual and saturation vapor pressure, free
P
POST /thermo/relative-humidity$0.002⚙️ Developer UtilitiesFree
Reynolds number calculator
Re=ρVL/μ, free
A
POST /thermo/reynolds-number$0.002⚙️ Developer UtilitiesFree
Specific heat capacity calculator
c = Q/(m·ΔT) from heat, mass and temperature change, free
A
POST /thermo/specific-heat-capacity$0.002⚙️ Developer UtilitiesFree
Heat conduction calculator
Q = k A ΔT / L through a wall, free
P
POST /thermo/thermal-conduction$0.002⚙️ Developer UtilitiesFree
Thermal efficiency calculator
η = (W/Q_in)×100% from work output and heat input, free
A
POST /thermo/thermal-efficiency$0.002⚙️ Developer UtilitiesFree
Arrival local time calculator
flight duration + UTC offsets, free
A
POST /travel/arrival-local-time$0.002⚙️ Developer UtilitiesFree
Average speed calculator
total distance over elapsed time free
A
POST /travel/average-speed$0.002⚙️ Developer UtilitiesFree
Travel points value calculator
cents per point vs baseline, free
P
POST /travel/award-value$0.002⚙️ Developer UtilitiesFree
Cycling time estimator
bike ride duration from distance and speed, free
P
POST /travel/cycling-time$0.002⚙️ Developer UtilitiesFree
Travel distance unit converter
kilometers, miles and nautical miles, free
A
POST /travel/distance-unit-convert$0.002⚙️ Developer UtilitiesFree
ETA calculator
estimated arrival clock time from departure, free
P
POST /travel/eta-calculator$0.002⚙️ Developer UtilitiesFree
MPG to L/100km converter
US MPG, imperial MPG and liters per 100 km, free
A
POST /travel/fuel-economy-convert$0.002⚙️ Developer UtilitiesFree
Luggage linear inches calculator
L+W+H and airline limit check, free
A
POST /travel/luggage-linear-inches$0.002⚙️ Developer UtilitiesFree
Luggage volume calculator
bag liters and cubic inches from L×W×H, free
A
POST /travel/luggage-volume$0.002⚙️ Developer UtilitiesFree
Airline miles value calculator
cents per point from cash fare and taxes, free
A
POST /travel/miles-to-points$0.002⚙️ Developer UtilitiesFree
Driving range remaining calculator
fuel or charge × economy, free
A
POST /travel/range-remaining$0.002⚙️ Developer UtilitiesFree
Road trip time calculator
driving time and arrival offset, free
P
POST /travel/road-trip-time$0.002⚙️ Developer UtilitiesFree
Speed unit converter
km/h, mph, knots, m/s, free
A
POST /travel/speed-unit-convert$0.002⚙️ Developer UtilitiesFree
Timezone offset difference
hours between two UTC offsets, free
P
POST /travel/timezone-offset-diff$0.002⚙️ Developer UtilitiesFree
Tire pressure by load calculator
adjust PSI for actual load, free
A
POST /travel/tire-pressure-load$0.002⚙️ Developer UtilitiesFree
Road trip cost split
fuel and tolls per passenger free
A
POST /travel/trip-cost-split$0.002⚙️ Developer UtilitiesFree
Trip fuel cost estimator
distance, MPG and fuel price, free
A
POST /travel/trip-fuel-cost$0.002⚙️ Developer UtilitiesFree
Walking time estimator
distance and pace to duration, free
A
POST /travel/walking-time$0.002⚙️ Developer UtilitiesFree
Amplitude, period & phase shift calculator
from A sin(Bx+C)+D
A
POST /trig/amplitude-period$0.002⚙️ Developer UtilitiesFree
Angle of elevation calculator
distance and height to angle, free
A
POST /trig/angle-of-elevation$0.002⚙️ Developer UtilitiesFree
Coterminal angle calculator
positive and negative within one turn
A
POST /trig/coterminal-angle$0.002⚙️ Developer UtilitiesFree
Degrees minutes seconds converter
DMS ↔ decimal degrees either way
P
POST /trig/dms-to-decimal$0.002⚙️ Developer UtilitiesFree
Double-angle calculator
sin(2x), cos(2x), tan(2x) from one angle
A
POST /trig/double-angle$0.002⚙️ Developer UtilitiesFree
Arccosine calculator
acos(x) in degrees and radians, free
A
POST /trig/inverse-cos$0.002⚙️ Developer UtilitiesFree
Arctangent calculator
atan and atan2 in degrees and radians
A
POST /trig/inverse-tan$0.002⚙️ Developer UtilitiesFree
Law of cosines angle finder
three sides to all angles, free
A
POST /trig/law-of-cosines-angle$0.002⚙️ Developer UtilitiesFree
Law of sines calculator
missing side or angle from a pair
A
POST /trig/law-of-sines$0.002⚙️ Developer UtilitiesFree
Polar to rectangular converter
r and θ to cartesian x, y
P
POST /trig/polar-to-rectangular$0.002⚙️ Developer UtilitiesFree
Reference angle calculator
degrees or radians, quadrant, free
A
POST /trig/reference-angle$0.002⚙️ Developer UtilitiesFree
Right triangle trig solver
one side and acute angle, free
A
POST /trig/right-triangle-trig$0.002⚙️ Developer UtilitiesFree
Sine cosine tangent calculator
sin, cos, tan, csc, sec, cot from an angle
P
POST /trig/sin-cos-tan$0.002⚙️ Developer UtilitiesFree
Sine wave calculator
amplitude, period, phase, vertical shift, value at x
P
POST /trig/sine-wave$0.002⚙️ Developer UtilitiesFree
Sum and difference angle calculator
sin cos tan of a±b, free
A
POST /trig/sum-difference$0.002⚙️ Developer UtilitiesFree
Exact trig values calculator
sin cos tan radicals for special angles, free
A
POST /trig/trig-exact-values$0.002⚙️ Developer UtilitiesFree
Miles to km converter
convert miles to kilometers, free
A
POST /conv/miles-to-km$0.002⚙️ Developer UtilitiesFree
Bearing and heading calculator
compass direction between two points
A
POST /trig/bearing$0.002⚙️ Developer UtilitiesFree
Feet to cm converter
convert feet to centimeters, free
A
POST /conv/feet-to-cm$0.002⚙️ Developer UtilitiesFree
Triangular number calculator
n-th triangle and membership test
P
POST /math/triangular-number$0.002⚙️ Developer UtilitiesFree
Harshad number checker
Niven test and quotient, free
A
POST /numth/harshad-number$0.002⚙️ Developer UtilitiesFree
Rate constant from rate law calculator
k from measured rate, free
A
POST /chem/rate-constant-from-rate$0.002⚙️ Developer UtilitiesFree
PEM Base64 encoder
64-char lines with BEGIN/END headers, free
P
POST /enc/base64-pem$0.002⚙️ Developer UtilitiesFree
Absence percentage calculator
days absent over scheduled workdays
G
POST /fin/absence-percentage$0.002⚙️ Developer UtilitiesFree
AAA triangle calculator
three angles and one side via law of sines
A
POST /math/aaa-triangle$0.002⚙️ Developer UtilitiesFree
Absolute humidity calculator
grams of water vapor per cubic meter, free
H
POST /phys/absolute-humidity$0.002🔍 Semantic Search & RAGAPI
Get text embeddings
for search, clustering and RAG
N
POST /search/embed$0.002🔍 Semantic Search & RAGAPI
Embed a whole corpus
one job, published price, or by API
N
POST /search/embed-batch$0.002🔍 Semantic Search & RAGAPI
Index your text
chunk, embed and store, no vector DB
N
POST /search/index-text$0.002🔍 Semantic Search & RAGAPI
Index PDFs and scans
into one searchable index
N
POST /search/index-document$0.010🔍 Semantic Search & RAGAPI
Index a website
crawl a site for semantic search
N
POST /search/index-url$0.040🔍 Semantic Search & RAGAPI
Search by meaning
not by keyword
N
POST /search/semantic$0.002🔍 Semantic Search & RAGAPI
Hybrid search
keyword and vector, fused into one ranking
N
POST /search/hybrid$0.002🔍 Semantic Search & RAGAPI
Rerank results
reorder by true relevance
N
POST /search/rerank$0.002🔍 Semantic Search & RAGAPI
Find similar documents
«more like this» for any corpus
N
POST /search/similar-docs$0.002🔍 Semantic Search & RAGAPI
Reverse image search
find similar images in your library
N
POST /search/similar-images$0.002🔍 Semantic Search & RAGAPI
Recommend related content
without a recommender team
N
POST /search/recommend$0.002🔍 Semantic Search & RAGAPI
Cluster texts
group thousands by theme
N
POST /search/cluster$0.002🔍 Semantic Search & RAGAPI
Detect outliers
find the records that don't belong
N
POST /search/outliers$0.002🔍 Semantic Search & RAGAPI
Match products
supplier SKUs to your catalogue
N
POST /search/match-products$0.002🔍 Semantic Search & RAGAPI
Ask your documents
answers grounded in your own files
N
POST /rag/answer$0.003🔍 Semantic Search & RAGAPI
Answers with citations
every claim traced to its source
N
POST /rag/answer-sources$0.003🔍 Semantic Search & RAGAPI
Chat with a PDF
ask questions, get cited answers
N
POST /rag/chat-pdf$0.003🔍 Semantic Search & RAGAPI
Chat with a website
a bot that only knows your site
N
POST /rag/chat-website$0.003🔍 Semantic Search & RAGAPI
Build an FAQ bot
answers from your help centre
N
POST /rag/faq-bot$0.003🔍 Semantic Search & RAGAPI
Rewrite queries
turn a vague question into a searchable one
N
POST /rag/query-rewrite$0.003🔔 Notifications & FlowsAPI
Send a transactional email
from your domain, with delivery events
N
POST /notify/email$0.002🔔 Notifications & FlowsAPI
Send email from a template
merge your variables
N
POST /notify/email-template$0.002🔔 Notifications & FlowsAPI
Email a file as attachment
deliver the invoice you just made
N
POST /notify/email-attachment$0.002🔔 Notifications & FlowsAPI
Schedule an email
send it later, cancel before it goes
N
POST /notify/email-scheduled$0.002🔔 Notifications & FlowsAPI
Turn an email into a webhook
attachments included
N
POST /notify/email-in$0.002🔔 Notifications & FlowsAPI
Batch events into one daily email
instead of fifty pings
N
POST /notify/digest$0.002🔔 Notifications & FlowsAPI
Deliver webhooks reliably
signed, retried, dead-lettered
N
POST /notify/webhook$0.002🔔 Notifications & FlowsAPI
Send a message to Slack
formatted, on web, email or API
N
POST /notify/slack$0.002🔔 Notifications & FlowsAPI
Post to a Discord channel
embeds, on web, email or API
N
POST /notify/discord$0.002🔔 Notifications & FlowsAPI
Route an alert to the right channel
deduplicated for you
N
POST /notify/alert$0.002🔔 Notifications & FlowsSoon
Chain tasks together
transcribe → summarise → publish, one job
N
POST /flow/chain$0.000🔔 Notifications & FlowsSoon
Run tasks in parallel
fan out, then join the results
N
POST /flow/parallel$0.000🔔 Notifications & FlowsSoon
Branch your workflow
decide on the previous step's result
N
POST /flow/conditional$0.000🔔 Notifications & FlowsAPI
Run one task over 100,000 items
batched, one job
N
POST /flow/batch$0.002🔔 Notifications & FlowsAPI
Schedule a task
run any KIT task on a cron schedule
N
POST /flow/schedule$0.002🔔 Notifications & FlowsAPI
Retry failed tasks
exponential backoff and a dead-letter queue
N
POST /flow/retry$0.002No capabilities match your search.
How it works
1
Get your key
Create an account with your email and add balance when you need it. No subscription, no sales call.
2
Call the endpoint
One authenticated POST. The API returns a task_id immediately — copy-paste snippets in five languages on every page.
3
Collect the result
Receive a signed webhook the moment it's ready, or fetch a signed link. A failed task is never charged.
Pay only for what you use
No subscription. Free tools run in your browser; paid tasks draw from your balance, which never expires.
Free tools
$0.00
On-device utilities — hash, QR, JSON, Text→PDF and more — run in your browser. No account, no limits.
Pay-as-you-go
Per task
$0.002+
The full API — 2015 capabilities — billed only for what you run, from $0.002 per call. No monthly fee.
Balance
$10.00+
Top up your balance and spend it across web, API and the app. It never expires.