Developer Tools

Regex tester, color picker, code formatters, JWT decoder, and more.

Browser-based utilities for web development: test a regular expression, decode and verify a JWT, compare two versions of a file, minify or tidy HTML, CSS and JavaScript, convert Markdown, and build colours, gradients and shadows for a stylesheet.

11 tools available · Free · No signup required

All 11 tools

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Regex Tester

Test regular expressions with live match highlighting.

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Color Picker

Pick colors and get HEX, RGB, HSL, and HSV values instantly.

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CSS Gradient Generator

Build beautiful CSS gradients visually and copy the code.

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Box Shadow Generator

Generate CSS box-shadow with a live visual preview.

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HTML Minifier / Beautifier

Minify or format HTML code with a single click.

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CSS Minifier / Beautifier

Minify or format CSS code instantly.

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JS Minifier / Beautifier

Minify JavaScript with Terser or format it with Prettier.

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Markdown to HTML

Convert Markdown to HTML with a live side-by-side preview.

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JWT Decoder

Decode and inspect JWT tokens — header, payload, and signature.

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Bcrypt Generator

Hash a password with bcrypt at the cost you choose, or check a password against any bcrypt hash.

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Diff Checker

Compare two text blocks and highlight the differences.

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Which tool to pick

Regex Tester: writing or debugging a pattern against real sample text, with each match highlighted as you type.
JWT Decoder: reading a token's header and claims, seeing whether it has expired, and verifying its signature with a secret or a public key.
Diff Checker: spotting what changed between two versions of a config file, an API response or a paragraph of copy.
JS Minifier / Beautifier: shrinking a script for production with Terser, or formatting minified code with Prettier so a person can read it.
Color Picker: converting a colour between HEX, RGB, HSL and HSV for whichever format your stylesheet uses.

Small tools in the middle of bigger jobs

Most of these get opened for a minute in the middle of something else. A failing login sends you to the JWT decoder to check the expiry and audience claims. A test fails on a long API response, so both versions go into the diff checker. A log parser misses lines, so its pattern goes into the regex tester with a few real log lines pasted underneath.

For styling, the colour picker and the gradient and box-shadow generators give you CSS to copy straight into a stylesheet, and the HTML and CSS formatters tidy inherited markup before you edit it. Markdown to HTML is handy for READMEs and release notes headed for a CMS or an email.

About Our Free Developer Tools

Our developer toolbox includes a regex tester, color picker, CSS gradient and box-shadow generators, HTML/CSS/JS minifiers and beautifiers, Markdown-to-HTML converter, JWT decoder, and a diff checker — all running 100% in the browser.

Built for front-end and full-stack developers who need quick utilities without leaving the browser. No backend, no latency, no data sent to servers. This matters for the JWT decoder in particular: tokens you paste are decoded locally and never transmitted anywhere.

All developer tools are completely free and require no login. Bookmark this page and save time on your everyday development workflow.