CSS Minifier

Every comment, indent and line break in a stylesheet is a byte your visitors download. Minification removes all of that formatting — plus shortens colours and drops the last semicolon in each block — while keeping the rules functionally identical, so pages load faster with zero visual change. This minifier processes your CSS right here: paste a stylesheet and see the compressed result together with the exact saving in bytes and percent. It handles the safe, standard optimisations (whitespace, comments, hex shortening, zero-unit trimming) without the risky rule-merging that can change cascade behaviour. Your stylesheets never leave your browser, which matters for unreleased designs.

Quick Answer: Paste CSS and get a minified stylesheet instantly, with the byte and percentage savings shown — rules unchanged, formatting gone.

Free Online Tool

Same styles, fewer bytes.

Your CSS

0 BOriginal

0 BMinified

0%Saved

Minified CSS

How to Use the CSS Minifier

Paste your stylesheet into the input box.
Press Minify CSS.
Compare the sizes shown: original versus minified, and the percentage saved.
Copy the minified CSS into your production file or build.
Keep the original somewhere safe — minified CSS is for machines, not for editing.

Key Features

Removes comments, indentation and unnecessary whitespace.
Shortens hex colours (#ffffff to #fff) and trims zero units where safe.
Reports original size, minified size and percentage saved.
Preserves rule order and cascade — no risky restructuring.
Runs locally, so proprietary stylesheets stay private.

Best Practices and Tips

Minify at deploy time from your readable source; never edit the minified file by hand.
Combine minification with gzip or Brotli on the server for the full saving — the two stack.
Check the saving percentage: tiny savings on a hand-written sheet are normal; huge ones suggest heavy commenting was inflating the file.
If a minified sheet breaks a page, the usual suspect is a licence comment or a source-map reference that a build actually needed — compare against the source.
Cache-bust minified files with a version query or hashed filename so returning visitors get the new rules.

Common Mistakes to Avoid

Minifying CSS that contains hacks relying on comments (old IE hacks) and wondering why legacy behaviour vanished.
Assuming minification fixes slow pages by itself — oversized images and fonts usually dwarf CSS savings.
Overwriting the only readable copy of a stylesheet with its minified version.
Minifying twice through layered tools, which occasionally corrupts strings containing comment-like sequences.

Frequently Asked Questions

Is minified CSS functionally identical?

Yes, when done with safe transforms like these. Whitespace, comments and redundant characters carry no meaning in CSS (outside strings), so removing them cannot change what a browser renders. This tool deliberately avoids merging or reordering rules, which is where risky minifiers can alter behaviour.

How much can I expect to save?

Typically 15 to 35 percent on a normally formatted stylesheet, before server compression. Heavily commented development files save more; already-tight files save less. The tool reports your exact figure.

What happens to URLs and strings in my CSS?

Quoted strings and url() contents are preserved verbatim — the minifier only compresses the structural whitespace around them, never the content inside quotes.

Should I minify CSS that a framework generates?

If you ship it to visitors, yes — the same byte logic applies. In modern build pipelines this happens automatically; this tool serves the same purpose for hand-managed sites and quick jobs.

Does it handle CSS variables and modern syntax?

Yes. Custom properties, grid, flexbox, media queries and nesting-free modern CSS pass through — the transforms are purely textual and do not need to understand the semantics of each rule.