Don's Tools · Developers · HTML, CSS & JS Minify & Beautify

Minify & beautify code

Format or compress HTML, CSS and JavaScript, right in your browser. Nothing is uploaded.

Language
Action
Works in your browser: formatting happens on your device with nothing uploaded. The first run loads a small formatter (js-beautify) or, for minifying JavaScript, the Terser engine; both are then cached.
Minify and Beautify is a free developer tool that formats and compresses HTML, CSS and JavaScript entirely in your browser, with nothing uploaded. Beautifying uses the js-beautify library, minifying JavaScript uses the Terser engine, and CSS and HTML are minified by safely removing comments and unnecessary whitespace, with the size reduction shown.

Frequently asked questions

Is my code uploaded anywhere?

No. Formatting runs entirely in your browser with nothing uploaded, so proprietary code stays on your device. A small formatter is loaded once and then cached.

Which languages are supported?

JavaScript, CSS and HTML, each with a Beautify and a Minify action.

What engines does it use?

Beautifying uses the well-known js-beautify library. Minifying JavaScript uses Terser, the same engine used by major bundlers, while CSS and HTML are minified with safe whitespace and comment removal.

Will minifying break my code?

JavaScript is minified with Terser, which is robust and reports a clear error if the code cannot be parsed. CSS and HTML minification only removes comments and unnecessary whitespace.

Can I download the result?

Yes. Copy it, or download it with the correct file extension for the language you chose.