CSS Minifier
Minify CSS — remove whitespace & comments
100% freeRuns in browserNo data sent to servers
Also try: AI Humanizer · AI Detector · Email Writer 3 free uses/day
How It Works
1
Paste CSS
Paste or upload .css.
2
Auto-minify
Whitespace and comments removed.
3
Copy
Copy or download.
FAQ
What does CSS minification do?
Removes whitespace, comments, and unnecessary characters from CSS to reduce file size.
Does it break my CSS?
No. Only safe removals: whitespace, comments, trailing semicolons. All rules are preserved.
How much reduction?
Typically 20-40% depending on formatting.
Is my code uploaded?
No. All processing in your browser.
Does it remove comments?
Yes. All CSS comments (/* */) are removed.
Does it merge duplicate rules?
No. It only removes whitespace and comments. Use a CSS optimizer for rule merging.
Can I upload .css files?
Yes.
Can I download?
Yes. Download as .css file.
Does it handle Sass/SCSS?
It processes the CSS syntax. Sass variables and nesting are preserved as-is.
Is there a size limit?
No practical limit.
Does it work on mobile?
Yes.
Does it remove vendor prefixes?
No. All prefixes (-webkit-, -moz-, etc.) are preserved.
Can it beautify CSS?
This tool minifies. For formatting, use a CSS beautifier.
Is it free?
Yes. See all <a href="/ai/dev">Developer Tools</a>. Also try <a href="/ai/dev/json">JSON Formatter</a>.
What other tools?
HTML Minifier, JS Minifier, JSON Formatter, and <a href="/ai/dev/diff">Diff Checker</a>, plus 20+ more.
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Minify CSS by removing whitespace and comments. All processing in your browser.