CSS Formatter
Validate, format, minify, and transform CSS — with strict error checking, custom sorting, vendor prefixes, and color conversions.
Key Features
Standard Style Presets
Standardize your project styling rules instantly using our built-in CSS style guides. You can choose from popular developer setups like Google, Airbnb, or standard library guidelines, or design a fully customized layout structure of your own. The formatting engine automatically configures space sizes, sets line breaks, adjusts selector indentation, and cleans up braces to match your team's code rules. This helps teams prevent formatting conflicts and keep style files clean, unified, and easy to review across all development systems.
Sort Properties
Improve your stylesheet structure and make editing easier. You can sort CSS properties alphabetically or group them by function. Grouped sorting organizes properties logically: layout styles (like display and flex) go first, dimensions and spacing (like width, margin, and padding) go second, text fonts and styles third, and visual decorations (like colors, borders, and animations) go last. This keeps your styles highly organized, helping developers find and tweak attributes quickly without endless scrolling.
Clean Units & Colors
Modernize your CSS files dynamically during formatting. Toggle the responsive unit converter to translate fixed pixel values (px) into modern relative values (rem or em) based on a custom font size (such as 16px). You can also convert back from rem or em units into pixels if needed. In addition, the tool normalizes all color definitions (like RGB, HSL, or color names) into a consistent HEX format, keeping your project's color palette uniform and matching responsive design rules.
View Style Rules Map
Navigate large stylesheets with thousands of lines using our interactive selector map. The parser builds a collapsible outline showing all media queries, keyframes, selectors, and declaration counts. Clicking any entry in the tree outline instantly focuses the editor on that exact style block, making adjustments simple. This helps front-end developers inspect complex setups, check nested layouts, and organize stylesheet rules efficiently.
Search Style Rules
Find specific rules instantly using our advanced filter tool. You can search by selector name, styling property, or color value. The utility updates search matches as you type, highlighting the exact lines in your stylesheet. This makes verifying utility classes, hunting down color overrides, and tracing layout variables across your file fast and simple. It supports regular expressions to locate advanced patterns in responsive style blocks.
Fix Browser Compatibility
Ensure your layout renders correctly on all web browsers without manual effort. Toggle the vendor prefix feature to automatically inject required browser tags (such as -webkit-, -moz-, -ms-, and -o-) for modern CSS layout structures like flexbox, grids, transitions, and filters. The prefix engine checks web compatibility databases to apply only the necessary prefixes, keeping your final stylesheet size small and clean.
Code Checker
Catch missing semicolons, unclosed brackets, and common typos before they break your website layout. The validator checks your CSS structure as you type, highlighting any error lines in the code view and showing clear explanations of how to fix them. The engine checks every rule block to ensure your code is valid, preventing layout bugs from slipping into production website templates.
Compress Code & Stats
Compress stylesheets for production release with a single click. The compressor removes comments, extra spaces, and redundant line breaks without changing the behavior of preformatted blocks or keyframe rules. Review the stats panel to compare file sizes, see total rules, track unique selectors, and measure compression rates. This helps you balance readability during development and loading speed for users.
Usage Examples
.card {
z-index: 10;
background-color: rgb(255, 255, 255);
width: 100px;
display: flex;
}.card {
background-color: #ffffff;
display: flex;
width: 100px;
z-index: 10;
}Common Use Cases
Standardizing Large Team Repositories
When multiple developers work on the same stylesheets, code formats can easily become messy and inconsistent. Code reviews can become cluttered with simple spacing and indentation differences. By applying alphabetical property sorting and standardizing brackets automatically, you ensure that all stylesheets follow the exact same format. This reduces merge conflicts in Git and allows your team to review styling logic rather than formatting details.
Modernizing Legacy Stylesheets
Converting old style files into responsive layout systems is tedious. Paste legacy CSS into the formatter to convert fixed pixels into rem units, standardize color schemes into consistent hex codes, and delete duplicate style declarations. This speeds up design updates, improves website scaling on mobile phones, and establishes clean variables that are easy to maintain, reducing design migration work.
Optimizing Production Bundle Sizes
Reduce file sizes to improve page loading speeds. The minification tool strips comments, styling spaces, and line breaks while keeping style logic intact. This makes your CSS files smaller, improving site metrics and reducing data usage for mobile users. The compiler outputs detailed file savings statistics so you can evaluate the optimizations before publishing code to the web.
How It Works
Load Code Input
Start by pasting your CSS code into the editor, uploading a local stylesheet file, or loading style data from a public URL. The editor loads the content immediately, tracks selector counts, and prepares the internal text buffer for styling transformations.
Set Formatting Rules
Choose your preferences, including space size, property sorting methods (alphabetical or grouped), unit conversions (pixel-to-rem ratios), vendor prefixes, and minification. The tool computes adjustments dynamically in the workspace as you change options.
Analyze CSS Structure
The background engine reads the CSS structure, reports syntax errors, and builds an interactive selectors map. Heavy files are parsed using background threads, keeping the browser interface responsive and smooth during operations.
Output and Statistics
Copy the formatted stylesheet or download it as a custom file. Check the metrics panel to verify total rules, unique selectors, average selector lengths, and file size savings. All operations run locally on your device to keep your data private.
Frequently Asked Questions
Grouped property sorting organizes declarations inside a CSS rule into logical categories rather than alphabetical order. The tool positions layout settings (like display, position, flex) first, box model attributes (width, margin, padding) second, typography variables (font, line-height) third, and visual decorators (color, background, border) last. This standardizes your selectors, making it easy to scan styles and find positioning properties immediately.
The vendor prefixer injects necessary prefixes (-webkit- for Safari/Chrome, -moz- for Firefox, -ms- for older Internet Explorer, and -o- for Opera) for layout features like transforms, keyframe animations, flexbox, user selection, and grid layouts. It checks compatibility databases to add only the necessary prefixes, preventing your stylesheet from becoming bloated with unneeded code.
This formatter is designed for standard CSS stylesheets. If your code includes nested blocks from Sass, SCSS, or Less, we recommend compiling them into standard CSS before formatting. Running raw nested stylesheets directly might cause syntax error highlights in the editor, as standard CSS does not support nested selector rules.
The converter calculates relative units based on your custom base font size, which is set to 16px by default. The tool divides pixel values (like 32px) by the base size (16px) to generate the corresponding relative value (2rem). You can easily change this base value in the options toolbar to match your project's custom design system guidelines.
Yes, the syntax validator fully supports modern CSS3 properties, including layout variables, custom variables, grid templates, media queries, keyframe animations, and filter properties. It checks your code for issues like missing closing brackets, unmatched curly braces, and unclosed comments, helping you write clean and correct stylesheets.
Yes, the tool fully supports converting rem and em units back to pixel values (px). Simply select the conversion option in the settings menu, set your base font size, and the formatter will recursively multiply relative values to generate absolute pixels, which is helpful when standardizing older static templates.