Tools

Turn text or an image into a grid of monospaced characters, shaded by brightness.

Real-time frequency bars from your microphone, with a test-tone fallback.

Numbers between binary, hex, decimal, octal and any radix from 2 to 36.

Text as binary, hex, octal and decimal, byte by byte, with a hex dump mode.

Build a linear, radial or conic gradient and copy the CSS.

Scientific and RPN calculator with memory, history, trig, log and constants.

Caesar, Atbash, Vigenère, ROT13 and Base64, encode or decode.

A wall of clocks across timezones, analogue and digital.

Simulate protanopia, deuteranopia and tritanopia on a colour or an image.

HEX, RGB, HSL and OKLCH in one place, with WCAG contrast.

A large picker surface with an eyedropper, saved swatches and WCAG contrast.

The classic cellular automaton. Click to seed cells, then run it.

Coordinates between decimal degrees and degrees-minutes-seconds.

Line-by-line comparison of two texts.

Shannon entropy over the raw UTF-8 bytes of your text.

Identify file types by magic bytes. Drop a file or browse the signatures.

Chromatic aberration, band displacement and noise, on text or an image.

Plot up to four expressions in x. No eval, no Function().

Convert between HTML entities, named codes and raw text.

SHA and MD5 digests for any string.

Pretty-print, validate, minify and traverse JSON.

Press any key to see its key, code, keyCode and modifiers.

Placeholder text by paragraph, sentence or word.

Write markdown, preview it live in a split pane.

Falling glyph columns: katakana, binary or ASCII.

Generate SEO and social meta tags with live preview cards.

Text to Morse and back, with audio playback.

Animated fractal value noise: FBM, turbulence and ridged, across six palettes.

Configurable password generator with live entropy scoring.

Paint, erase and bucket-fill a small grid, then export a PNG.

Check primality, find factors, hunt nearby primes.

A QR encoder written from scratch. Byte mode, versions 1-10, EC level L or M.

Test regular expressions with live match highlighting.

Drag two markers to measure a distance in CSS pixels.

A command shell in the browser with a virtual filesystem, pipes, redirection and three operating systems to choose from.

Twelve case formats at once: upper, lower, camel, snake, kebab and the rest.

A countdown with an alarm, and a stopwatch with laps you can copy out.

Unix epoch seconds to readable dates and back, across timezones.

Percent-encode and decode URLs, and parse query strings.

Generate v4 and other UUIDs, one click each.

Length, mass, temperature, speed and volume, metric and imperial.

An oscilloscope and frequency analyser fed by your mic or a test signal.

Word count, letter frequency, reading time and top words.