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CSS Minifier & Beautifier

This CSS Minifier & Beautifier helps you optimize stylesheets for production and format CSS for debugging. Choose Minify to remove whitespace and reduce file size, Beautify to reformat CSS with clean indentation, or Remove Comments to strip comment blocks without changing the rules.

Minified CSS loads faster and reduces bandwidth, especially on mobile and when your site has multiple CSS files. Beautifying is useful when you’re working with minified vendor CSS or trying to understand messy output from plugins and themes. Paste your CSS, run the operation, then copy or download the result. If your CSS fails to minify, it’s usually due to invalid syntax such as missing braces, unterminated comments, or broken @media blocks.

Format and Optimize CSS Code

Operation Type

Input CSS

Output CSS

How to minify or beautify CSS

  1. Paste your CSS into Input CSS (or upload a file).
  2. Select an operation: Minify CSS, Beautify CSS, or Remove Comments.
  3. Click the action button.
  4. Copy or download the output.

CSS minifier examples (before and after)

Example: Minify CSS

/* Buttons */ .button { padding: 12px 16px; background: #2d6cdf; color: white; }

.button{padding:12px 16px;background:#2d6cdf;color:#fff}

Example: Beautify CSS

.container{max-width:1200px;margin:0 auto;padding:0 16px}

.container { max-width: 1200px; margin: 0 auto; padding: 0 16px; }

Best practices

  • Keep a readable source version for development; minify only for production.
  • If you use WordPress caching plugins, avoid double-minifying the same file.
  • Validate CSS after minifying if the source comes from unknown plugins/themes.
  • Use long-term caching with versioned filenames when deploying minified CSS.

Troubleshooting

ProblemLikely causeFix
Output is emptyInvalid CSS, missing bracesValidate input and fix syntax errors
Minify breaks layoutSource CSS already broken or relies on hacksCheck original, remove hacky rules, re-test
@media rules not appliedBroken @media blockEnsure braces match and blocks are closed
Comments not removedNon-standard comment formatUse proper /* ... */ blocks

Common questions

What is the difference between minify and beautify?

Minify removes whitespace/comments to reduce file size for production. Beautify formats CSS with indentation and line breaks for readability while debugging.

Should I minify CSS on WordPress?

Yes, but avoid double-minifying if you use caching/minification plugins. Keep a readable source and minify only once for production delivery.

Can minifying CSS break calc() or CSS variables?

Minification should not change behavior, but invalid CSS or edge-case hacks can break. If layout changes, validate your original CSS and test after minifying.

Does removing comments change CSS behavior?

Removing standard /* ... */ comments doesn’t change how CSS rules work, but be careful if comments are used as tool directives in your build pipeline.

What if my CSS minify output is empty?

That usually means the input CSS has syntax errors (missing braces, unterminated comments, or broken @media blocks). Fix the source, then retry.

Can this tool minify SCSS or LESS?

No. SCSS/LESS are preprocessors. Compile them to plain CSS first, then minify the resulting CSS.

How much does CSS minification reduce size?

It often reduces file size by ~20–40% depending on formatting and comments. Heavily commented or well-indented CSS usually compresses more.

Should I use this tool or cssnano in a build pipeline?

For production pipelines, cssnano (or similar) is best. This tool is great for quick fixes, debugging, and one-off optimizations.

What is the best way to cache minified CSS?

Use long-term caching with versioned filenames (e.g., style.min.css?v=123 or hashed filenames) so browsers keep caches until you deploy changes.

Can I minify inline CSS?

Yes. Paste the CSS and minify, then copy the output back into your HTML or template.

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