CSS Minifier — CSS minification removes comments, collapses whitespace, drops the last semicolon in a rule, and tightens the spaces around punctuation. The result is a CSS file that is functionally identical to the source but typically 20-40% smaller.
CSS never leaves your browser.
Was CSS Minifier useful?
What is css minifier?
CSS minification removes comments, collapses whitespace, drops the last semicolon in a rule, and tightens the spaces around punctuation. The result is a CSS file that is functionally identical to the source but typically 20-40% smaller.
Use this when you have a hand-written stylesheet and want a quick minified copy without setting up a build pipeline. For production projects, run your CSS through a proper tool (cssnano, lightningcss) as part of your build.
How to use it
-
Paste your CSS
A snippet, a file, or an entire stylesheet.
-
Read the result
The minified CSS appears instantly.
-
Copy
One click to put the minified CSS on your clipboard.
Examples
Comment stripping
A simple comment-and-whitespace example.
/* header */ .a { color: red; } Result: .a{color:red}
Punctuation tightening
Spaces around { } ; : , are removed.
a , b > c { color : red ; } Result: a,b>c{color:red}
Perguntas frequentes
Comparison: this tool vs the alternatives
Uttir CSS Minifier vs CSSNano (CLI)
| Feature | Uttir | CSSNano (CLI) |
|---|---|---|
| No upload to a server | ✓ | ✓ |
| No signup / no install | ✓ | ✗ |
| No build pipeline required | ✓ | ✗ |
| Removes whitespace + comments | ✓ | ✓ |
| Advanced transforms (merge rules, optimize calc) | ✗ | ✓ |
| Run in browser, copy paste ready | ✓ | ✗ |
Related guides
How to Build a CSS Grid Layout (with Real Examples)
A practical guide to CSS Grid: when to use it (and when flexbox is the better choice), the six properties that matter, how named lines and areas work, and how to experiment with a live layout in your browser before committing it to a stylesheet.
The 8 Best Free CSS Tools in 2026 (No Signup, No Upload)
A curated list of the best free CSS tools: gradient generators, box-shadow builders, flexbox / grid playgrounds, minifiers, and animation builders. All run in your browser.
How to Minify HTML, CSS, and JavaScript Without Breaking Your Site
Minification shrinks your HTML, CSS, and JavaScript files by removing whitespace, comments, and dead code. Learn what it does, what it does not do, when to use it, and how to safely minify a file in your browser without uploading the source.
Ferramentas relacionadas
HTML Minifier
Shrink HTML by stripping comments and collapsing whitespace. See byte savings in real time.
JavaScript Minifier
Quick JS minifier that strips comments and collapses whitespace. Best for trusted, simple code snippets.
JSON Formatter
Format, beautify, and validate JSON with adjustable indentation — instantly in your browser.
Last reviewed: 2026-09-24