CSS minifier

Free CSS Minifier — Compress Your Stylesheets

This tool minifies your CSS by removing the unnecessary characters — whitespace, line breaks, comments and redundant syntax — that bloat a stylesheet without changing how it renders. Paste your CSS and get back a smaller, identical-working version ready to ship.

CSS sits in the critical rendering path, which makes minifying it especially worthwhile. Browsers typically need to download and parse your CSS before they can paint the page, so a leaner stylesheet means the browser reaches "ready to render" sooner. The comments and generous spacing that keep your source readable add bytes every visitor must download for zero visual benefit. Stripping them shrinks the file, speeds up transfer and parsing, and combines with Brotli or Gzip compression for a further reduction — all of which supports faster loads and better Core Web Vitals.

Use this tool to minify a stylesheet before deploying, to quickly compress a CSS file you're working on, or to check how much excess weight your styles carry. For one-off tasks it's perfect; for ongoing projects, building minification into your asset pipeline ensures every release ships compressed automatically. Pair it with removing unused CSS rules for the biggest wins — the less your stylesheet weighs, the faster your pages feel.

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