Minify CSS with one click. Preserve important comments, merge rules safely, and download production-ready styles.
CSS Minifier — Compress, Clean & Optimize Your Styles Instantly
Tired of bulky stylesheets slowing your site? Our CSS Minifier crushes unnecessary characters, spaces, and comments to deliver production-ready CSS that loads fast and keeps your layout pixel-perfect. Paste your CSS, choose options, and get a compact file in a click—no sign-up, no fluff.
Why Minify CSS?
- Faster loads: Smaller files reduce render-blocking time and improve Core Web Vitals.
- Lower bandwidth: Save data on every request, especially on mobile.
- Cleaner builds: Ship optimized, consistent styles to production.
- Better SEO: Speed boosts UX signals search engines value.
Key Features
- Aggressive whitespace & comment stripping with safe defaults
- Optional rule & property merging to reduce repetition
- Autofix minor formatting quirks (e.g., trailing semicolons)
- Preserve important comments (
/*! ... */
) when enabled - Duplicate selector/property cleanup (optional)
- URL minification inside
url()
(optional) - @media normalization to remove redundant spaces
- One-click copy & download of minified output
- 100% client-side processing—your code never leaves the browser
How It Works
- Paste your CSS into the input panel.
- Pick options (preserve important comments, merge rules, etc.).
- Minify to compress instantly.
- Copy or Download the minified CSS for production use.
Before & After (Example)
Input
<style>
/* Main theme */
:root {
--brand:#4c7cff; /* primary */
}
.button {
color: #ffffff ;
background-color: #4c7cff ;
padding: 12px 20px ;
border-radius: 8px ;
}
</style>
Output
<style>
:root{--brand:#4c7cff}.button{color:#fff;background-color:#4c7cff;padding:12px 20px;border-radius:8px}
</style>
Options & Safe Defaults
- Preserve
/*! important */
comments: Off by default. Enable to keep licenses/credits. - Merge duplicate rules & properties: On by default, safe merges only.
- Normalize zero values: Convert
0px
→0
. - Shorten colors: Convert
#ffffff
→#fff
when safe. - Trim quotes in
url()
: Only when safe; keeps data URIs intact.
Compatibility
- Output works in all modern browsers.
- No vendor prefixes added/removed—pair with your PostCSS/Autoprefixer pipeline if needed.
- Unicode & RTL safe; does not change token order in a way that affects specificity.
Performance Tips
- Serve minified CSS with HTTP/2 and gzip/brotli.
- Inline critical CSS in
<head>
; defer the rest. - Audit unused styles with your build tools to reduce size further.
- Combine minification with caching and a CDN for best results.
Privacy
Everything runs locally in your browser. We don’t upload or store your styles—period.
Frequently Asked Questions
Will minification change how my site looks?
No. Minification removes whitespace, comments, and other non-rendering characters. Optional merges are safe by default.
Can I keep license comments?
Yes. Enable "Preserve important comments" to keep /*! ... */
blocks required for licensing.
Do I still need Autoprefixer?
Yes. Minification does not add vendor prefixes. Use Autoprefixer if you support older browsers.
Does this tool upload my CSS?
No. Processing is 100% client-side in your browser; nothing is uploaded or stored.