Free CSS Formatter Online
Format messy or minified CSS instantly — runs in your browser, nothing uploaded.
Input CSS
Formatted CSS
CSS Formatting Examples
Minified CSS is hard to read; formatting adds indentation and line breaks. Example:
Container and button styles
Minified input:
Formatted output:
Click Sample above to load minified CSS into the editor.
What Is a CSS Formatter?
You copy a stylesheet out of DevTools or get a minified CSS file from a build — and it's one solid wall of text. No line breaks, no indentation, just a nightmare to read. A CSS formatter fixes that: it parses your CSS and adds proper indentation and line breaks so you can actually see the selectors, properties, and nesting. The MDN CSS reference and W3C CSS spec define the rules the language follows. Whether you're debugging Bootstrap's compiled output, reviewing third-party CSS, or cleaning up a stylesheet before a code review, formatting makes it legible in seconds. Popular tools like Prettier do the same in your editor — this tool does it instantly in the browser, no setup needed. CSS-Tricks has a solid collection of guides on CSS structure and best practices. For browser compatibility context, Can I Use is the go-to resource.
This tool parses your CSS and reformats it with consistent indentation. It runs entirely in your browser. Nothing is sent to a server, so it's safe to use with production stylesheets. For minifying CSS, use the CSS Minifier. For validation, use the CSS Validator.
How to Use This Tool
Paste or Upload
Copy your CSS and paste it into the left editor. You can also click Upload to load a .css file. The Sample button loads example data. Invalid CSS will show an error.
Check the Output
The right panel updates automatically. Valid CSS gets formatted with proper indentation. Use Minify to remove whitespace and get a compact version for production.
Copy or Download
Use Copy to put the result on your clipboard, or Download to save it as a file. For SCSS or Less, use SCSS to CSS or Less to CSS to compile first.
How the Formatter Works
The tool parses your CSS and reformats it with consistent indentation. Selectors, properties, and rules are detected; braces and semicolons are preserved. The W3C CSS specifications define the language. Formatting adds line breaks and spaces for readability without changing behavior. At-rules like @media, @keyframes, and @import are handled. Processing runs in your browser—nothing is sent to a server.
Build tools like Vite, Webpack, or Parcel often output minified CSS. Pasting that output here makes it readable. For SCSS or Less source, compile first with SCSS to CSS or Less to CSS, then format.
When CSS Formatting Helps
Most developers need a formatter when inspecting styles from production sites, debugging third-party CSS, or reviewing minified output from build tools. Pasting compressed CSS here makes selectors and rules visible immediately. Bootstrap or Tailwind compiled output is often minified—formatting reveals the structure. You can use Claude or ChatGPT to generate CSS for complex layouts, then format the output here for readability.
Formatting also helps before sharing styles with teammates or reviewing pull requests. For adding vendor prefixes, use the CSS Prefixer. For converting to inline styles (e.g., for email), use CSS to Inline. For validation, use CSS Validator.
Frequently Asked Questions
Is my data private?
Yes. Formatting runs entirely in your browser. No data is sent to any server. You can confirm this by opening your browser's Network tab.
Does it support SCSS or Less?
This tool formats plain CSS. For SCSS or Less, compile first using SCSS to CSS or Less to CSS, then format the output.
What does Minify do?
It removes whitespace, newlines, and comments from the formatted output, giving you the smallest version for production. There's also a dedicated CSS Minifier page.
Does it preserve comments?
Formatting preserves comments. Minifying may remove them depending on the minifier. Check the output before using in production.
What about CSS custom properties?
CSS variables (--var-name) are supported. The formatter handles modern CSS syntax including custom properties, @media, and @keyframes.