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CSS Minifier

Minify CSS code online. Remove whitespace, comments, and unnecessary characters to reduce file size.

What is a CSS Minifier?

A CSS minifier compresses your stylesheets by removing unnecessary characters — comments, whitespace, line breaks, and redundant semicolons — without changing functionality. Minified CSS loads faster, reduces bandwidth costs, and improves your website’s Core Web Vitals scores, which directly affects SEO rankings.

Modern websites often ship CSS files that are 50-80% smaller after minification. Our free online CSS minifier processes your code instantly in the browser — no data leaves your machine, and there’s no file size limit for practical use.

How to Use This CSS Minifier

  1. Paste your CSS into the input text area
  2. Click “Minify” to compress the stylesheet
  3. Review the output — the minified CSS preserves all styling rules
  4. Copy the result and use it in your production build
  5. Check the size reduction shown in the output stats

Common Use Cases

  • Production deployment — Minify CSS before deploying to reduce page load times
  • Email templates — Compress inline CSS for HTML emails where every byte counts
  • Performance optimization — Reduce CSS file size to improve Largest Contentful Paint (LCP) scores
  • Quick one-off minification — When you don’t have a build pipeline set up yet
  • Comparing file sizes — See how much space your comments and formatting actually use

Frequently Asked Questions

Does minifying CSS break anything?

No. Minification only removes characters that don’t affect how the browser interprets your CSS. Comments, extra spaces, and unnecessary semicolons are stripped, but all selectors, properties, and values remain intact.

Should I minify CSS if I’m already using gzip compression?

Yes. Minification and gzip work together — minification removes redundant characters, and gzip compresses the remaining text. Together they typically achieve 85-95% reduction from the original file size.

What about CSS source maps?

For debugging minified CSS in production, generate a source map alongside your minified file. Most build tools (webpack, Vite, PostCSS) do this automatically. This tool is best for quick minification tasks.