CODE · COMPATIBILITY · FILE SIZE

Optimize JavaScript and CSS for browsers

Transform JavaScript syntax for current browsers or ES5, and adapt supported modern CSS features for selected browser targets while keeping output readable.

Switch to the separate compressor to minify JS or CSS. Open local files, review the output, then copy or download it. Processing stays on your device.

Full mode is active — all options are available.

01 / CODE PROCESSOR LOCAL · NO UPLOAD

Choose a mode and code type

The current-browser target keeps modern syntax where supported. JavaScript API polyfills are not added.

Advanced options

Parse as an ES module (import / export) Preserve function and class names Remove console calls Remove debugger statements

Source code

Code to process

📁 Open a .js or .css file

Result

Choose a code type, enter source, and select a mode.

The tool parses and transforms code but never executes it. Browser compatibility still depends on APIs and features used by your project.

ABOUT THIS TOOL

What this JavaScript and CSS tool can do

The optimization mode targets syntax and browser compatibility while preserving readable formatting. The compressor uses local AST-based processors to reduce code size.

JavaScript: transform modern syntax for current browsers or ES5; minify with optional name preservation and removal of console/debugger statements.
CSS: lower supported modern syntax and add compatible fallbacks for browser targets; minify CSS with the same target profile.
Open .js, .mjs, .cjs, or .css files up to 5 MB. Review, copy, or download UTF-8 output.
All processing runs locally in the browser. Source code is not executed and is not sent to the server.