CSS Minifier | Compress & Optimize CSS
Strip whitespace and comments, collapse shorthands, and shorten values to reduce CSS size and speed up page loads. Supports Grid/Flexbox, custom properties, media queries, and keyframes—everything runs locally in your browser.
How to Use This Tool
- 1
Paste your CSS into the input area.
- 2
Use Live mode for instant minification (or Manual mode to click Minify).
- 3
Review original vs. minified size and compression stats.
- 4
Copy or download the minified CSS.
- 5
Verify in your app before deployment.
Use Cases & Examples
Production Build Optimization
Integrate minification into your CI/CD to shrink bundles and speed up page loads.
Website Performance & Core Web Vitals Optimization
Reduce CSS bytes to improve LCP, INP, and overall loading performance.
Bandwidth & Hosting Cost Reduction
Serve fewer bytes at scale to lower CDN and hosting costs.
CSS Framework & Library Optimization
Remove unused styles (PurgeCSS) and then minify CSS from frameworks like Bootstrap or Tailwind.
CSS Minification Basics
Minification eliminates formatting and comments, normalizes zeros/units, compresses colors, and merges compatible declarations without changing computed styles.
It complements Gzip/Brotli by shrinking the pre-compressed source, improving transfer, parse, and execution times that affect Core Web Vitals.
Typical savings are 30–50%. Always test minified output and automate minification in production builds.
Frequently Asked Questions
Q.What if minified CSS doesn't work correctly?
A. Output should behave the same; issues usually come from non-standard hacks. Test before deploy and keep an unminified source for debugging.
Q.Should I minify CSS during development or only for production?
A. Write readable CSS during development and minify for production—ideally via your build pipeline or CI.
Q.How do I generate source maps for debugging minified CSS?
A. This tool doesn’t emit source maps. Use build tools (e.g., webpack + css-minimizer, Vite, or PostCSS cssnano) when you need maps.
Q.What optimizations does CSS minification perform?
A. Removes whitespace/comments, deduplicates rules, merges shorthands, normalizes zeros and colors, and strips redundant syntax while preserving behavior.
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