How to use CSS Minifier
- Paste the stylesheet.
- Keep or disable the value optimisations.
- Copy or download the minified CSS.
CSS Minifier features
- Removes comments, whitespace, final semicolons and empty rules
- Shortens hex colours (#ffffff → #fff) and leading zeros (0.5em → .5em)
- Drops units on zero lengths outside calc()
- Keeps strings, url() contents and calc() spacing intact
- Optionally preserves /*! license */ comments
- Reports bytes saved
CSS Minifier example
Minify a rule
Input:
body {
margin: 0px;
color: #333333;
padding: 0.5rem;
}Output:
body{margin:0;color:#333;padding:.5rem}Frequently asked questions about CSS Minifier
What optimisations are applied?
Whitespace and comments are removed, the last semicolon in each block is dropped, empty rules are deleted, six-digit hex colours are shortened when possible (#ffffff → #fff), leading zeros are trimmed (0.5em → .5em) and zero lengths lose their unit outside calc().
Is calc() safe?
Yes. Spaces around + and − inside calc() are required by the CSS spec and are preserved; zero units inside functions are also kept (calc(100% - 0px) stays valid).
Can I keep a license comment?
Yes. Comments that start with /*! are kept by default.
Does it merge duplicate rules or shorthand properties?
No. Structural optimisations can change the cascade, so the minifier deliberately keeps every rule in place.