CSS Minifier
Shrink CSS by removing comments and unnecessary whitespace, with brace-balance validation so you always know your rules are sound.
Updated September 2026 · Written and verified by Akash Pandey
CSS Minifier
How to use the CSS minifier
- Paste your CSS into the input.
- Choose options: keep or remove comments, collapse whitespace, and merge adjacent same-selector rules.
- Click Minify - size savings are shown and unbalanced braces produce a clear error line.
Frequently asked questions
What does the CSS minifier remove?
Comments, bulk whitespace and newlines, and - with the option - merges adjacent rules that share a selector. Values inside strings are preserved exactly.
How is malformed CSS handled?
Braces are counted and balanced per at-rule; an unbalanced block is reported with the approximate location rather than passed through corrupted.
Is the space-after-colon in declarations safe to remove?
Yes - "color: #fff" and "color:#fff" are identical CSS. The minifier also normalizes that consistently.
How much smaller will my CSS get?
Typical savings are 15-40% after the obvious formatting, more on heavily commented and indented stylesheets.
Can I use the output in production?
Yes - the produced CSS is standards-compliant and safe to serve. There is no build-time or runtime dependency.
Is it free?
Yes, and it runs fully in-browser with no data leaving your device.
Does CSS minification affect media queries and keyframe animations?
No. Media query rules and @keyframes blocks are preserved with exact syntax, removing only unnecessary whitespace and comment blocks.
Can CSS minification break specificity or cascade rules?
No. This conservative minifier does not reorder rule declarations or combine selectors, ensuring your styling cascade remains 100% identical.