Free online tools
Converters, calculators and generators — all free, all in your browser, no signup needed.
Measurement
Universal Unit Converter
Length, distance and volume between metric & imperial units, plus gauge matching
Weight Converter
Convert kg, grams, pounds, ounces, stones and tons
Temperature Converter
Celsius, Fahrenheit and Kelvin temperature conversions
Speed Converter
m/s, km/h, mph, ft/s, knots and mach
Shape Calculator
Area, perimeter, volume and radius for 2D & 3D shapes with SVG diagrams
Paper Size
A-series, B-series, C-series and US paper sizes with SVG scale diagram
BMI Calculator
Body Mass Index from height and weight, metric or imperial
Files
File Archive Creator
Compress and archive files into ZIP, TAR and GZ formats
Image Converter
Convert images between JPG, PNG and WebP, resize, crop and compress to an exact file size — free and private, right in your browser
Batch Image Processor
Bulk convert, resize and export multiple images at once — JPG, PNG, WebP
Image to Mosaic
Turn a photo into a tiled mosaic, with an optional Mosaic-finity mode
Collage Maker
Arrange multiple images into a collage and export as PNG, JPG or PDF
PDF Toolkit
Merge, split, extract and rotate PDFs, turn images into a PDF, or export pages as JPG/PNG — free and private, right in your browser
Finance
Currency Converter
Live exchange rates for 20+ world currencies
Interest Calculator
Simple and compound interest with visual growth charts
Wage Calculator
Compare hourly, daily, weekly and annual salaries
Utilities
Percentage Calculator
Percentage of values, change, increase and decrease
Numeral Converter
Big numbers in words, Roman, scientific, engineering, Mayan, Chinese and Babylonian
Encryption & Hashing
SHA-256, SHA-512, bcrypt, Argon2id, PBKDF2 and more
Encode / Decode
Encode or decode text as Base64, Hex, Binary, Base32 or URL encoding
QR Code Generator
Turn any link or text into a QR code — PNG or SVG, custom colours, print sizes
Password & UUID Generator
Generate strong random passwords and UUIDs
Steganography
Hide and extract secret messages inside images
Color Converter
Convert HEX, RGB, HSL, HSV and CMYK colour formats
Color Palette Generator
Generate complementary, analogous, triadic & more colour palettes
Text Case Converter
UPPERCASE, Title Case, camelCase, snake_case and more, plus word/character counts
Word & Character Counter
Count words, characters, sentences and paragraphs live, with reading time, keyword density and social media character limits
Time & Date
Unix Timestamp
Convert Unix timestamps to human-readable dates and back, with a live clock
Date Calculator
Days between two dates, or add/subtract days, weeks, months and years
Electronics
Storage Size
Convert between bits, bytes, KB/MB/GB (SI decimal) and KiB/MiB/GiB (IEC binary)
Ohm's Law
Solve Ohm's Law for Voltage, Current, Resistance or Power
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