CSS Minifier

Get a reliable result in three steps

1. 1

   Paste or load a complete CSS stylesheet in the CSS source editor.

2. 2

   Select Minify CSS to remove block comments and unnecessary spacing.

3. 3

   Review the minified stylesheet, then copy or download it after confirming required notices were retained elsewhere.

What this tool does

CSS Minifier removes block comments and unnecessary spacing from a CSS stylesheet while preserving quoted string content. It processes CSS only; JavaScript has a separate purpose-built minifier.

The result is produced only after the input is checked. If the value cannot be processed, the workspace reports a specific error instead of guessing.

Example

/* Card theme */
.card, .notice {
  color: #223c88;
  margin: 0 1rem;
  content: "Spacing inside strings is preserved";
}

Limitations

• Review important output before using it in production.
• Very large inputs remain subject to browser memory limits.
• This tool performs conservative text minification; it does not rewrite selectors, merge declarations, optimize values, or provide full CSS grammar validation.
• All CSS block comments are removed, including licence or attribution comments, so retain required notices separately before minifying.