CSS Minifier
Minify CSS code by stripping comments, collapsing whitespace, removing unnecessary semicolons, and compressing selectors. The tool shows you the original and minified file sizes side by side with the exact percentage saved. Typical savings range from 20-40% depending on how the CSS is formatted. Minified CSS loads faster because browsers download fewer bytes and parse the stylesheet more quickly. Use this before deploying to production, when inlining styles in HTML emails, or when optimizing above-the-fold critical CSS. All processing runs in your browser — your stylesheets are never uploaded to any server.
How to Use
- 1
Paste Your CSS
Enter or paste the CSS code you want to minify. You can paste an entire stylesheet or just a section — there is no size limit beyond your browser memory.
- 2
Click Minify
Press the Minify button to strip all comments, collapse whitespace, remove unnecessary semicolons, and compress your CSS into a single line.
- 3
Review the Stats
Check the original size, minified size, and percentage saved. Typical reduction is 20-40% depending on how your CSS is formatted.
- 4
Copy the Result
Copy the minified output to your clipboard and paste it into your production build, CDN, or HTML file.
Examples by Niche
Minify a 50KB stylesheet to ~35KB (30% reduction) before uploading to your server. Smaller CSS means faster page loads and better Core Web Vitals scores.
Extract and minify above-the-fold CSS to inline in your HTML head tag, eliminating render-blocking stylesheet requests for faster first paint.
Minify CSS for HTML emails where file size directly affects deliverability. Many email providers have size limits, and smaller emails avoid spam filters more reliably.
Minify custom CSS added via a CMS theme customizer when the platform does not provide built-in minification.
Frequently Asked Questions
What does CSS minification remove?
Minification removes all comments (both single-line and block), extra whitespace and newlines between rules, unnecessary semicolons (like the last one before a closing brace), and redundant spaces around selectors and properties. The result is a single continuous line of CSS that browsers parse identically to the original.
Will minification break my CSS?
No, minification only removes characters that have no effect on how browsers interpret the stylesheet. Selectors, property names, values, and the cascade order all remain unchanged. The visual rendering is pixel-identical to the original.
How much file size can I save?
Savings depend on the formatting of your original CSS. Well-commented, neatly indented stylesheets typically see 25-40% reduction. Already compact CSS might only shrink 10-15%. The tool shows exact before/after byte counts so you can measure the improvement.
Should I minify CSS for development or only production?
Keep your CSS readable during development for easier debugging. Minify only for production builds. Most build tools (Vite, webpack, PostCSS) handle this automatically, but this tool is useful for one-off tasks, quick tests, or projects without a build pipeline.
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