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CSS Minifier

Strip comments and collapsible whitespace from CSS.Developer Tools

CSS Minifier

Strip comments and collapsible whitespace from CSS. A conservative pass: strings, url() values and property semantics are untouched.

About this tool

A deliberately conservative pass: comments and redundant whitespace only. Strings and url values are untouched, so the output is safe to ship without a full parser.

How to use the CSS Minifier tool

  1. Paste your CSS. Any stylesheet.
  2. Minify. Comments and spacing collapse.
  3. Copy the output. Production-ready text.

Supported formats

Input

  • Plain text or file input

Output

  • Converted or analysed output

Inputs are validated before anything is processed. Invalid values and unsupported files are rejected with a clear error instead of failing silently.

Frequently asked questions

Why not a full minifier?

Minification is kept to whitespace and comments because deeper optimisation risks changing meaning.

Are vendor prefixes touched?

No. Only whitespace and comments.

How much smaller?

Typically 20 to 40 percent for comment-heavy stylesheets.

Privacy

Everything you enter stays in this browser tab. There is no upload endpoint for tool inputs, no account, and no server-side copy of your text or files. Results are produced locally and disappear when you close the page.

No account is required and no file is ever uploaded. See the privacy policy for details about analytics and the limited data this site stores.

Known limitations

  • No nesting, autoprefixing or property merging.

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