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Developer Tool
CSS Minifier
Your CSS stays in your browser. Not uploaded.
Input
Output
Minified CSS will appear here
Frequently asked questions
Will minification break my CSS?
No. Our minifier only removes unnecessary whitespace, comments, and redundant semicolons. It does not alter any CSS rules, selectors, or values.
How much size reduction can I expect?
Typically 15–30% depending on how much whitespace and comments your CSS contains. Well-commented CSS sees the biggest reductions.
Should I minify CSS in development?
No. Keep your CSS readable during development. Minify only for production builds to improve page load speed.
Does this support CSS variables and modern syntax?
Yes. The minifier is syntax-agnostic and handles CSS custom properties (variables), grid, flexbox, and all modern CSS features.