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About This Tool
The CSS Minifier shrinks stylesheet file sizes by removing code comments, redundant spaces, and indentation line breaks.
Production web applications minify CSS to decrease asset download payloads, improve Time to First Contentful Paint (FCP), and conserve mobile data bandwidth.
### How CSS Minification Works 1. Comment Removal: Strips all multiline comment blocks (/* ... */) from the stylesheet source. 2. Whitespace Collapsing: Reduces consecutive spaces, tabs, and line feeds down to single spaces. 3. Delimiter Compression: Removes whitespace surrounding selector opening braces, closing braces, property colons, semicolons, and commas.
### Concrete Minification Example Paste unminified stylesheet rules: ```css /* Header navigation bar */ .nav-bar { display: flex; margin: 0px; padding: 12px 16px; } ```
The tool outputs a single compressed line: `.nav-bar{display:flex;margin:0px;padding:12px 16px;}` slashing file bytes while retaining identical styling behavior in the browser.
### Processing and Privacy All minification regex operations execute entirely inside your web browser. No stylesheet files or CSS rules are uploaded to external servers.
How to Use
- 1
Paste your unminified CSS into the left "UNMINIFIED CSS" panel, or click to load sample code.
- 2
Click "Minify CSS" to strip comments and redundant whitespace.
- 3
Review the compressed output in the right "MINIFIED CSS" panel and copy to clipboard.
Frequently Asked Questions
Does minifying CSS alter how styles render on web pages?
No. Minification only strips extraneous whitespace and comments. Browsers parse minified CSS rules into the same CSSOM tree as unminified code.
Should I minify CSS during development or production?
Keep original unminified files with comments for local development and editing, and serve minified files in staging and production builds.
Are my project stylesheets saved on a server?
No. All compression runs strictly inside your local browser runtime.