CSS Minifier
Minify CSS whitespace, shorten values, and merge compatible rules. Retain top-level /*! comments and check the result against your original stylesheet.
CSS Minifier
Minify CSS whitespace, shorten values, and merge compatible rules. Retain top-level /*! comments and check the result against your original stylesheet.
About CSS Minifier
Parse, compress, and regenerate
The CSS minifier parses the stylesheet into an AST, runs compression passes, and then generates compact CSS again. This lets it remove redundant structure more carefully than simple whitespace stripping.
Check production CSS quickly
Use it when you need a compact stylesheet for a demo, a static snippet, or a quick before-and-after size check. Keep the readable source in your repository and treat the minified output as a deployable artifact.
FAQ
Common questions and answers about this topic.
What does CSS minification do?
The CSSO engine removes unnecessary whitespace and ordinary comments, shortens values, and merges compatible rules. It retains /*! comments only at the top level of the stylesheet; comments inside rules or @media blocks are removed. To preserve a license notice, place it in a top-level /*! ... */ comment and check the output.
Will minification break my CSS?
The engine aims to preserve styling, but it does more than remove formatting: it can rewrite values and restructure rules. Keep the original CSS and check the result in your target browsers before deployment, especially when using newer CSS syntax.
How much can file size be reduced?
There is no fixed reduction percentage. It depends on whitespace, comments, repeated rules, and whether the input is already minified. Already compact CSS may shrink very little. Compare your own input and output rather than assuming a typical saving.
Is CSS minification browser-only?
No. This CSS minifier uses server-side processing for its compression engine, so avoid pasting private or sensitive stylesheets.