DevToolNow

CSS Minifier & Beautifier

Minify CSS to reduce file size, or beautify it for readability. 100% client-side — your code never leaves your browser.

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What is CSS Minification?

CSS minification removes whitespace, newlines, comments, and redundant characters from CSS source code without changing the browser's behavior. The result is a smaller file that loads faster, parses faster, and contributes to better Core Web Vitals — particularly LCP (Largest Contentful Paint), since CSS is render-blocking.

Why bytes matter

Browsers can't render any text on the page until they've downloaded and parsed the CSS in <head>. Every kilobyte adds to the time before First Contentful Paint. On 3G mobile (~250 KB/s effective), saving 50 KB of CSS saves 200 ms of render time. Compounded across millions of page views, minification is one of the highest-leverage performance wins.

Minify vs gzip vs Brotli

These complement each other. Minification removes redundant characters at the source level — readable minified CSS still benefits from compression on top. Gzip (default for HTTP) compresses the already-minified bytes ~50% further. Brotli (modern alternative) gives another 5–15% over gzip for text content. Always do all three: minify → gzip/Brotli → cache.

⚠️ Reference Only

Output is generated based on your input and is provided for reference. Results may vary depending on your specific use case, edge cases, or environment-specific behavior. We do not guarantee accuracy of conversions, validations, or computed values.

Always verify critical outputs against official documentation or production environments. We are not responsible for any decisions or losses based on these tool results.