CSS Minifier

Minify and compress CSS code by removing comments, whitespace and unnecessary characters. Reduce file size, improve load times and keep your styles production-ready.

⚡ Client-side processing only 🧮 Shows size & savings 🔒 No code is uploaded
Original CSS Paste your formatted or unformatted CSS here
Minified CSS Result after minification (single-line or compact output)
Original Size
0 B
0 lines
Minified Size
0 B
0 lines
Saved
0 B
0% compression

Free Online CSS Minifier & Compressor

The CSS Minifier from PowerSEOTools.online helps you compress and optimize your stylesheets in a single click. By removing comments, line breaks, extra spaces and unnecessary characters, you can significantly reduce CSS file size and improve your website’s loading speed.

Minified CSS is ideal for production environments, CDNs, and any performance-focused deployment where human readability is less important than file size.

Why Minify CSS?

Every extra kilobyte of CSS needs to be downloaded by the browser before your page is fully rendered. Minification reduces file size without changing how your styles work.

  • Faster page loads: Smaller CSS files download quicker, especially on mobile and slower connections.
  • Better Core Web Vitals: Optimized assets help improve metrics like LCP (Largest Contentful Paint).
  • Bandwidth savings: Less data transfer for you and your visitors over time.
  • Cleaner production builds: Ship readable CSS in development and minified CSS in production.

What This CSS Minifier Does

  • Removes comments: Strips out /* comment */ blocks from your CSS.
  • Collapses whitespace: Reduces extra spaces, tabs and line breaks to a compact form.
  • Trims unnecessary characters: Removes redundant semicolons and spaces around punctuation where safe.
  • Keeps strings intact: Preserves text inside quotes so URLs and content values remain valid.
  • Shows savings: See original size, minified size and total bytes saved with an estimated compression percentage.

How to Use the CSS Minifier

Getting started takes just a few seconds:

  • Paste your CSS into the Original CSS box (or type directly).
  • Click Minify CSS to run the optimizer in your browser.
  • View the result in the Minified CSS box.
  • Use Copy Minified CSS to copy the result into your project, or Download to save a .min.css file.
  • Check the stats panel to see how much size you saved.

Privacy-Friendly, Client-Side Minification

All processing is done using JavaScript in your browser. Your stylesheets are not uploaded or stored on any server. This makes the tool safe for private projects, proprietary code and client work.

Best Practices for Production CSS

  • Keep a readable, formatted version of your CSS in your source code repository.
  • Use the minified version (style.min.css) on live sites and CDNs.
  • Combine minification with HTTP compression (Gzip/Brotli) at the server level.
  • Remove unused CSS where possible to keep file size small.
  • Use this tool alongside other utilities on PowerSEOTools.online such as the Page Speed Analyzer and URL Encoder/Decoder for broader optimization.