CSS Minifier
Minify CSS online: remove comments and needless spaces to cut stylesheet size for faster loads. Instant, private, and safe for your rules.
This tool runs entirely in your browser. Your data never leaves your device — it is not uploaded to any server.
How to use
- 1Paste your CSS into the input box.
- 2The minified output appears instantly, with the size saved shown below.
- 3Copy the compact stylesheet or clear the input to minify another file.
CSS Minifier
Paste any stylesheet and get a compact one-line version in real time: comments are stripped, redundant whitespace collapses, and separators tighten up — while the contents of strings, url() values and your selector/property semantics remain exactly as written.
Use it to prepare critical CSS, slim down a theme before committing, or check how many bytes a cleanup would actually save. The live size readout shows input size, output size and the percentage saved.
Frequently asked questions
Will minification change how my CSS behaves?
No. Only comments and whitespace are removed — and even those carefully: strings and url() contents are preserved byte-for-byte, so content values and data URIs stay intact.
Does it optimize colors, merge rules or autoprefix?
No — this is a safe, syntax-level minifier. Structural optimization (merging duplicate rules, shortening colors) needs a full postprocessor; this tool guarantees zero semantic change.
Where does my CSS go?
Nowhere. Minification runs locally in your browser; nothing is uploaded or stored.
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Embed this tool
Put this tool on your own site with one line — it runs entirely in the visitor's browser.
<iframe src="https://zoyku.com/en/tools/css-minifier?embed=1" width="100%" height="640" style="border:0;border-radius:16px" title="Zoyku — css-minifier" loading="lazy"></iframe>