CSS Minifier
Minify CSS online for free — strip comments and whitespace to shrink file size, with string literals and calc() spacing safely preserved. Runs in your browser.
100% private — runs entirely in your browser. Your files never leave your device.
Strips comments and collapses whitespace while protecting string literals and calc() spacing,
so the output stays valid. Everything runs in your browser — your CSS is never uploaded.
How to use the CSS Minifier
- Paste your CSS.
- It's minified instantly, keeping strings and calc() intact.
- Check the before/after size saved.
- Copy or download the .min.css.
What you can use it for
- Shrink CSS to speed up your site
- Strip comments and whitespace safely
- Prep stylesheets for production
- Minify privately — no uploads
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Wrangling code or data?
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Browse all free developer tools →Frequently asked questions
How much smaller will my CSS get?
It depends on formatting and comments, but 20–50% is common. The tool shows the before/after size and percentage saved.
Will minifying break my CSS?
No — string literals and calc() spacing are protected, so the output stays valid. Only comments and non-significant whitespace are removed.
Is my CSS uploaded anywhere?
No — minification happens entirely in your browser.
Can I download the result?
Yes — copy it or download a .min.css file.