Developer

CSS Minifier

Shrink a CSS file by removing comments and unneeded whitespace, without changing what it does.

CSS

Minified CSS

How to use the css minifier

Paste your CSS into the input box.
Click Minify.
Copy or download the compact stylesheet.

Features

Removes CSS comments
Collapses whitespace around braces, colons and semicolons
Copy or download as a .css file

What CSS minification changes

Minification removes comments and unnecessary spacing so a stylesheet transfers fewer bytes. It does not redesign the page or make slow selectors faster; its main benefit is reducing the amount of text sent to the browser.

Keep an unminified source file for maintenance and use the minified copy for deployment. If your CSS uses unusual syntax, generated code or build-tool placeholders, test the output in your site before replacing the production stylesheet.

If you deploy through a CDN, use versioned filenames or a cache-busting strategy when the minified stylesheet changes. That avoids browsers holding an older cached file after you publish an update.

Performance also depends on how much CSS the page actually uses. Removing unused framework rules can save more bytes than minifying a stylesheet that still contains large blocks of unnecessary code.

Frequently asked questions

No, only formatting characters are removed. Selectors, property names and values are left exactly as written, just without extra whitespace.

Yes — keep your original, readable CSS as the source you edit, and run it through this tool only when producing the file you deploy.

Related tools

HTML Minifier

Strip comments and unnecessary whitespace from HTML markup.

JavaScript Minifier

Reduce JavaScript file size with a light, safe minifier.

JSON Formatter

Format, minify and validate JSON with clear error locations.

Base64 Encoder / Decoder

Encode text to Base64 or decode a Base64 string back to text.

Minify after development, not during it

Minified CSS is harder to read and debug. Keep an editable source file in version control and use minification as a delivery step after the stylesheet works correctly.

Test the minified output on the pages that depend on it.
Keep source maps if your build process supports them.
Do not assume a smaller file fixes render-blocking; delivery and critical CSS strategy still matter.