CSS Minifier
Minify and compress CSS instantly in your browser — no upload, no server, no setup. Removes all comments, whitespace, and unnecessary characters while preserving the exact rendering behaviour of your stylesheet. Shows the size reduction percentage so you can see the impact.
How to Use the CSS Minifier
- 1
Paste your CSS
Paste your CSS stylesheet into the input text area — any valid CSS including media queries, variables, and keyframe animations.
- 2
Click Minify
Click "Minify" to compress the output. The size reduction percentage is shown.
- 3
Optionally beautify
Click "Beautify" to format the CSS back to a readable form if needed.
- 4
Copy the result
Click "Copy" to copy the minified CSS to your clipboard for use in production.
Key Features
Private
Your stylesheets — including proprietary design system tokens — never leave your browser.
Size Savings
Typical 20-50% reduction shown as a percentage so you can measure the impact.
Safe Minification
Only removes whitespace and comments — never alters CSS logic or rendering behaviour.
Pro Tips
CSS minification should always be combined with Brotli or GZIP compression at the server level — compression typically achieves an additional 70-80% reduction on top of minification.
This tool performs safe whitespace removal. For advanced optimisation (removing unused rules, merging selectors), use cssnano or clean-css in your build pipeline.
Bootstrap's CSS compresses ~16% from minification alone — hand-written CSS with comments and generous spacing can achieve 40-50%.
Privacy Note
All processing in this tool runs entirely in your browser — no data is transmitted to any server. Your input is never logged, stored, or shared. This tool is free to use with no account or registration required.
Frequently Asked Questions
Related Developer Tools
Your input is processed locally in your browser and is never stored, transmitted, or shared with any server. See our Privacy Policy.