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CSS Minifier

⚙️ Minification Options
📝 Input CSS
Lines: 0 Size: 0 B
✅ Minified Output
Lines: 0 Size: 0 B

💡 Quick Examples - Click to Try

Basic Styles
.button { padding: 10px 20px; background: #007bff; color: white; }
Responsive Design
@media (max-width: 768px) { .container { width: 100%; } }
CSS Animation
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
Flexbox Layout
.flex { display: flex; justify-content: center; align-items: center; }
⚡

Maximum Compression

Reduce CSS file sizes by 30-70% through intelligent whitespace removal and optimization techniques.

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Color Optimization

Automatically converts colors to shortest format (#ffffff → #fff) for maximum space savings.

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Advanced Options

Customize minification with granular control over comments, whitespace, colors, and zero values.

✨

Beautify & Format

Reverse minification to restore readable, properly indented CSS for easier maintenance.

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Detailed Statistics

Track compression ratios and byte savings with real-time size comparison metrics.

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Client-Side Processing

All minification happens in your browser. Your CSS files never leave your computer.

About Our CSS Minifier Tool

Optimize your stylesheets instantly with our advanced free online CSS minifier and compression tool designed for modern web development. CSS minification is crucial for improving website performance, reducing page load times, and decreasing bandwidth consumption by removing unnecessary characters, whitespace, comments, and redundant code while preserving full functionality and maintaining cross-browser compatibility. Our powerful CSS minifier provides intelligent compression with comprehensive customizable options including removal of CSS comments and developer annotations for cleaner production code, elimination of unnecessary whitespace, line breaks, and indentation, optimization of color codes to shortest format converting #ffffff to #fff and #ff0000 to red where shorter, removal of trailing semicolons from the last declaration in each rule block, optimization of zero values.

Frequently Asked Questions

What is CSS minification and why should I use it?
CSS minification is the process of removing unnecessary characters from CSS code without changing its functionality. This includes removing comments, whitespace, line breaks, and optimizing values like colors and zeros. You should use CSS minification because it reduces file size by 30-70% on average, which leads to faster page load times, improved Core Web Vitals scores that affect SEO rankings, reduced bandwidth costs for high-traffic websites, better mobile performance on slower connections, and faster CSS parsing by browsers.
Will minifying CSS break my website's styling or layout?
No, proper CSS minification never breaks styling or layout functionality. Our minifier intelligently preserves all critical CSS features including whitespace in content properties and attribute selectors, proper spacing in calc() expressions and complex selectors, vendor prefixes for browser compatibility, media query conditions and breakpoints, keyframe animation definitions and timing functions, pseudo-classes and pseudo-elements, and CSS variables (custom properties).
How much file size reduction can I expect from CSS minification?
File size reduction varies significantly based on your CSS's original formatting style and comment density. Well-formatted CSS with proper indentation typically achieves 30-50% reduction, heavily commented development CSS can see 50-70% reduction, already compact CSS may only achieve 15-25% reduction, CSS frameworks like Bootstrap or Tailwind can see 40-60% reduction, and CSS with verbose color codes and zero values exceeds 60% reduction.
Should I minify CSS inline in HTML or external stylesheet files?
The best approach depends on your specific use case and architecture. For small amounts of critical CSS (under 1-2KB), minify and inline it directly in the HTML <head> to eliminate an HTTP request and improve initial render time.
Can I reverse CSS minification if I need to edit it later?
Yes, our tool includes a beautify feature that can reverse minification and restore readable formatting with proper indentation and line breaks. However, beautification has limitations: it cannot restore removed comments as those are permanently deleted during minification.