CSS Minifier - Compress CSS Online and See the Size Saved
CSS Minifier
Compress CSS and see exactly how many bytes you save
Real Compression
Removes whitespace and comments, shortens colors (six-digit hex codes become three digits where possible) and values (0px becomes 0) and drops quotes and units that are not needed.
Merges Rules
Rules with identical declarations are combined and duplicate media queries are joined, which often saves more than whitespace removal.
See the Savings
The original size, minified size, percent saved and gzipped size are shown, so you know what visitors will actually download.
Private
Your stylesheet is processed in your browser with the csso library. It is never uploaded.
Why Minify CSS
Browsers must download a stylesheet before they can show the page, so every byte counts, especially on mobile connections. Minifying removes everything the browser does not need, such as indentation, comments and redundant units, without changing how the page looks. Most sites also serve CSS compressed with gzip or Brotli, so check the gzipped figure, which is closer to what is really transferred.
The restructure option lets csso merge and reorder rules for a smaller result. It is designed to keep the cascade intact, but if your CSS depends on an unusual rule order, untick it for a safer, simpler minification and compare the page before you deploy. Comments starting with /*! are usually license notices, so they are kept unless you ask to remove everything.
Key Takeaways
- Keep your original: Minified CSS is hard to edit. Keep the readable source and minify as part of publishing.
- Gzip matters more than you think: Minified files still compress further, and the gzipped size shows the real saving.
- Related tools: Use the CSS Formatter to make minified CSS readable again.