What does a CSS minifier do?

A CSS minifier removes everything a browser does not need to render styles—comments, line breaks, extra whitespace, and redundant characters—producing a smaller file that downloads faster and improves page load time without changing how the styles behave.

How do I convert minified CSS back to normal?

Paste the minified CSS into the input and click Format. The formatter re-indents the rules and adds line breaks, turning one-line compressed CSS back into readable code for editing, debugging, and code review.

Does minifying CSS change how my styles look?

No. Minification only removes characters the browser ignores, such as comments and whitespace. The selectors, properties, and values stay identical, so your rendered styles look exactly the same while the file is smaller.

Is my CSS uploaded to a server?

No. All minifying and formatting runs entirely in your browser using client-side code. Your stylesheet never leaves your device, which keeps proprietary or sensitive CSS private.

How much smaller will my CSS file get?

It depends on how much whitespace and how many comments the original file contains. Heavily commented or generously formatted stylesheets often shrink by 20–50%, and the savings increase further once your server applies gzip or Brotli compression.

CSS Minifier & Formatter Online Free - Minify or Beautify CSS

Minify CSS online to shrink file size, or beautify it for editing. Free browser-based CSS compressor and formatter with instant results and no upload.

Paste your CSS and this tool instantly minifies it—stripping comments, whitespace, and redundant characters to shrink the file size for faster page loads. Switch to Format mode to beautify compressed or one-line CSS into readable, indented code for editing and debugging. Everything runs in your browser, so no stylesheet is ever uploaded to a server.

Why Use an Online CSS Minifier and CSS Formatter?

Use this CSS minifier to shrink stylesheets for faster loading, or switch to the CSS formatter to beautify code for debugging, refactoring, and reviews.

Format

Compress or format CSS code.

Minify

Use this CSS minifier to shrink stylesheets for faster loading, or switch to the CSS formatter to beautify code for debugging, refactoring, and reviews.

How to Use the CSS Minifier and Formatter

1
Paste your CSS
Enter or paste your stylesheet code into the CSS input field—from a single rule to an entire stylesheet.
2
Choose Minify or Format
Click Minify to compress CSS into a single compact line, or Format to beautify minified CSS back into readable, indented code.
3
Review the result
Inspect the converted output; invalid CSS is flagged so you can fix syntax before copying.
4
Copy the output
Use the Copy button to grab the minified or formatted CSS for your project, then Clear to start over.

References

MDN — CSS
Mozilla's reference for CSS syntax, properties, and values—useful for verifying rules after minifying or formatting.
W3C — CSS Snapshot
The W3C's official overview of the CSS specifications that define valid stylesheet syntax.

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JSON Formatter

Beautify and validate JSON data with proper indentation.

Frequently Asked Questions

What does a CSS minifier do?: A CSS minifier removes everything a browser does not need to render styles—comments, line breaks, extra whitespace, and redundant characters—producing a smaller file that downloads faster and improves page load time without changing how the styles behave.
How do I convert minified CSS back to normal?: Paste the minified CSS into the input and click Format. The formatter re-indents the rules and adds line breaks, turning one-line compressed CSS back into readable code for editing, debugging, and code review.
Does minifying CSS change how my styles look?: No. Minification only removes characters the browser ignores, such as comments and whitespace. The selectors, properties, and values stay identical, so your rendered styles look exactly the same while the file is smaller.
Is my CSS uploaded to a server?: No. All minifying and formatting runs entirely in your browser using client-side code. Your stylesheet never leaves your device, which keeps proprietary or sensitive CSS private.
How much smaller will my CSS file get?: It depends on how much whitespace and how many comments the original file contains. Heavily commented or generously formatted stylesheets often shrink by 20–50%, and the savings increase further once your server applies gzip or Brotli compression.