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Developer & Utilities

CSS Minifier & Beautifier

Minify CSS to shrink file size, or beautify minified/messy CSS into clean code — with live byte savings. Runs in your browser, nothing uploaded. Free.

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💡 About this tool

  • Minify strips comments and whitespace to shrink your CSS for production.
  • Beautify re-indents minified or messy CSS so it is readable again.
  • Runs in your browser — your CSS is never uploaded.

Free CSS Minifier & Beautifier

Minify CSS to shrink file size for production, or beautify minified and messy CSS back into clean, readable code. Paste your styles, click Minify or Beautify, and copy the result with a live before/after byte count. Everything runs in your browser, so your CSS stays private.

What does minifying CSS do?

Minifying CSS removes everything the browser does not need to render your styles — comments, line breaks, indentation, and unnecessary spaces — without changing how the page looks. It also trims small redundancies like the final semicolon in a rule. The result is a smaller stylesheet that downloads faster, which improves page speed and Core Web Vitals.

What does beautifying CSS do?

Beautifying does the reverse: it takes minified or untidy CSS and re-formats it with clean indentation, one declaration per line, and each selector on its own line. It is ideal for reading a minified stylesheet, cleaning up CSS exported from a tool or builder, or making a teammate's styles consistent before you edit them.

How to use the CSS minifier and beautifier

Both directions take one click:

  • Paste your CSS into the input box.
  • Click Minify to compress it, or Beautify to format it.
  • Choose your indent size for beautifying.
  • Check the byte savings, then copy or download the result.

Why minified CSS helps performance and SEO

Stylesheets are render-blocking resources — the browser must download and parse them before it can paint the page. Smaller CSS means the browser gets to first paint sooner, which lifts your PageSpeed score and the page-experience signals that feed SEO. Minification pairs perfectly with gzip or Brotli compression on your server; together they can dramatically cut the bytes sent to each visitor.

Is it safe to minify my CSS?

Yes. Minification only removes characters that do not affect how styles are applied, so your design renders identically. This tool preserves values that matter, keeps !important intact, and removes only redundant whitespace and comments. Because it runs entirely in your browser, nothing you paste is uploaded, making it safe for proprietary or unreleased styles.

Pro tip

Keep a readable, beautified stylesheet in source control and serve the minified version to visitors — ideally generated by your build step. For quick one-off pages or fixes, this tool is the fastest way to minify before publishing or beautify before debugging. For markup, see our HTML Minifier & Beautifier.

FAQ

Is this CSS Minifier free and private?
Yes. It is completely free and runs entirely in your browser, so your CSS is never uploaded or stored.
What is the difference between minifying and beautifying CSS?
Minifying removes comments and whitespace to make the file as small as possible for production. Beautifying adds indentation and line breaks to make the CSS readable for editing.
Will minifying change how my site looks?
No. Minification only removes characters the browser ignores, so your styles render exactly the same while downloading faster.
Does minifying CSS improve SEO?
Indirectly, yes. CSS is render-blocking, so smaller stylesheets speed up page rendering. Faster pages score better on Core Web Vitals, which supports SEO — especially combined with gzip or Brotli compression.
Does it keep !important and important values?
Yes. The minifier preserves !important and all meaningful values, removing only redundant whitespace, comments, and the trailing semicolon in each block.
Can I beautify minified CSS back to readable code?
Yes. Paste minified CSS and click Beautify to re-indent it with clean line breaks and your chosen indent size.
How much smaller will my CSS get?
It depends on how much whitespace and how many comments your stylesheet contains. The tool shows the exact byte savings and percentage after each minify.

Related tools

Pro tip: pair this tool with Upside Down Text Generator and Text Similarity Checker for a faster SEO workflow.