CSS/JS Minifier
Minify your CSS and JavaScript code to reduce file size and improve web performance. Automatically removes whitespace, comments, and unnecessary characters.
Did you know?
- Minification removes spaces, comments, and unnecessary characters
- Minified code is functionally identical to the original
- For JavaScript, use sourcemaps in production for easier debugging
- Always test your minified code before production
CSS/JS Minifier: Compress Your Code for Better Performance
The CSS/JS Minifier is a free online tool that compresses your CSS and JavaScript code by removing unnecessary characters. Reduce file sizes by 20-70% without changing functionality, improving website load times and reducing bandwidth costs.
Minification removes whitespace, comments, and shortens variable names while preserving code behavior. This tool processes your code entirely in the browser, ensuring your source code remains private and never touches any server.
How to Use
- Select the code type: CSS or JavaScript
- Paste your source code in the left text area
- Click "Minify" to start compression
- View the statistics: size before/after and reduction percentage
- Copy the minified code with the copy button
- Check for any syntax errors reported by the tool
💡 Why Minify Code?
Every kilobyte matters for web performance. Unminified CSS and JavaScript contain formatting, comments, and long variable names that are essential for development but unnecessary for browsers. Minification removes this overhead.
The benefits are significant: faster page loads, lower bandwidth costs, better Core Web Vitals, and improved user experience, especially on mobile networks.
🎯 Typical Use Case:
Your main JavaScript bundle is 500KB unminified. After minification, it's 180KB - a 64% reduction. Combined with gzip compression, the actual transfer size drops to under 60KB, dramatically improving load times.
🔧 Practical Use Cases
🚀 Production Deployment
Minify CSS and JS before deploying to production servers.
bundle.js: 500KB → 180KB (64% reduction)
📧 Email Templates
Inline minified CSS in email templates to reduce size.
styles.css: 15KB → 8KB (47% reduction)
📱 Mobile Optimization
Reduce payload size for faster mobile loading.
Critical CSS: 20KB → 7KB
🔍 Quick Optimization
Quickly minify code snippets without build tools.
Paste code → Get minified version
✨ What Gets Removed?
CSS Minification
- • Whitespace and line breaks
- • Comments (/* ... */)
- • Redundant semicolons
- • Unnecessary quotes
- • Zero units (0px → 0)
JavaScript Minification
- • Whitespace and line breaks
- • Comments (// and /* */)
- • Shortened variable names
- • Dead code removal
- • Statement optimization
❓ Frequently Asked Questions (FAQ)
Does minification break my code?
Minification should never change functionality. If your minified code doesn't work, it usually indicates a syntax error in the original code (like a missing semicolon) that the minifier exposed.
Should I minify during development?
No. Keep your development code readable with comments and formatting. Only minify for production builds. Most build tools (Webpack, Vite, etc.) handle this automatically.
What about source maps?
Source maps allow browsers to map minified code back to original source for debugging. This tool doesn't generate source maps - for that, use build tools like Webpack or esbuild in your development pipeline.
Minification vs Compression - what's the difference?
Minification removes unnecessary characters from source code. Compression (gzip, Brotli) is applied by servers to reduce transfer size. Use both for maximum benefit - minify your code, then let your server compress it.