Minify CSS stylesheets online for free. Remove whitespace, comments, and redundant rules to optimize your CSS for production. No signup required.
First time here? Paste your CSS code Your input is processed locally and disappears when you close the tab.
Stylesheets accumulate comments, indentation, and repeated rules that make them easy to maintain but slower to download. Our free CSS Minifier is a production-grade css minifier online that compresses your styles to the smallest safe size, improving page load speed and Core Web Vitals without changing how a single element renders.
Rather than blindly deleting characters, this tool parses your CSS with the csso engine, so it can compress css code intelligently, merging and restructuring rules while safely preserving calc() expressions, url() references, custom properties, and quoted string values. Paste any stylesheet to minify css online and instantly see the original and minified byte counts with the percentage saved, a reliable way to reduce css file size for frameworks, component libraries, and hand-written sheets alike. As a modern css optimizer it understands nesting, @layer, and the latest syntax, and finished output can be copied or downloaded as a .css file for your build.
Everything happens locally in your browser, so your design system and unreleased styles are never uploaded anywhere. Combine it with our HTML Minifier and JavaScript Minifier to compress the whole front end at once, or design fresh styles with the CSS Box Shadow Generator and CSS Gradient Generator before minifying them here.
Paste your CSS code
Click Minify
See the compressed output with size reduction stats
Copy the minified CSS