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🗜️ CSS Minifier

Paste your CSS and minify it instantly — comments are stripped, whitespace collapsed, and strings plus url() values are kept intact. See exactly how many bytes you save.

Your CSS
Basic minifier — strings & url() are preserved.

About

This CSS minifier runs entirely in your browser using a tokenization approach that correctly handles edge cases. It strips single-line (//) and multi-line (/* */) comments, collapses sequences of whitespace to a single space or removes them around punctuation such as { } : ; , and >, and preserves the content of quoted strings and url() values so that spaces inside data URIs or font names are never corrupted. Because it is a basic tokenizer rather than a full AST parser, it is fast and dependency-free, suitable for the vast majority of hand-written or preprocessor-generated CSS. The tool displays the original size, minified size, and bytes saved so you can make an informed decision about whether further optimization is needed.

How to use

  1. Paste your CSS into the input area on the left.
  2. Click Minify — the tool tokenizes your CSS and outputs a compressed version on the right.
  3. Check the size summary to see the original size, minified size, and how many bytes were saved.
  4. Click Copy to copy the minified CSS to your clipboard, or use Download to save it as a .css file.

FAQ

Does this tool process my CSS on a server?
No. Minification runs entirely in your browser with JavaScript. Your CSS is never sent anywhere.
Will minification break my CSS?
The tokenizer protects quoted strings and url() values, so valid CSS should survive intact. However, this is not a full AST parser — unusual edge cases in non-standard syntax may not be handled perfectly.
Are single-line // comments removed?
Yes. Both // single-line and /* */ multi-line comments are stripped. Note that // is not officially part of the CSS spec but is common in preprocessor source files.
How much smaller will my CSS get?
Typical hand-written CSS shrinks by 20–40%. Files with many comments or generous whitespace save more. For maximum compression, pair this with gzip or Brotli on your server.
Can I minify CSS with variables or calc() expressions?
Yes. Custom properties (--var), var(), calc(), and other modern CSS functions are treated as regular token values and pass through safely.