Compress and optimize CSS and JavaScript code for production.
The CSS & JS Minifier removes unnecessary whitespace, comments, and redundant code from your CSS and JavaScript files to reduce their file size. Smaller files load faster, improving your website's performance and user experience. This free online tool handles both CSS and JavaScript minification with instant results and a clear compression report.
Minification is the process of removing all unnecessary characters from source code without changing its functionality. This includes whitespace, newlines, comments, and redundant syntax. The result is functionally identical code that occupies significantly less disk space and transfers faster over the network to your users' browsers.
This tool supports both CSS and JavaScript minification in a single interface. Switch between modes using the tabs at the top, paste your code, and click Minify to get the compressed output instantly. The compression stats panel shows you exactly how much space you saved and the percentage reduction achieved.
Unlike build tools that require configuration and setup, this online minifier works immediately with no installation required. It's ideal for quick one-off tasks, verifying minification output, or working on projects where a full build pipeline isn't set up yet. The download button lets you save the minified file directly with the correct .min.css or .min.js extension.
The minifier is designed to be as simple as possible — paste your code and get compressed output in seconds.
Minification is a standard step in web development workflows and applies to a wide range of situations.
Always keep your original, unminified source files in version control. Minified code is not meant to be edited directly — it's a build artifact. Your development workflow should always work from the readable source files, with minification applied as a final step before deployment or as part of an automated build process.
Minification and server-side compression (gzip or Brotli) are complementary techniques that work together. Minification reduces the logical size of the code by removing unnecessary characters, while gzip compression reduces the transmitted size by encoding repeated patterns. Applying both gives you the maximum possible reduction in file size. Most web servers and CDNs apply gzip automatically, so minifying your files first ensures you get the best of both techniques.
For ongoing projects, consider integrating minification into your build pipeline using tools like webpack, Vite, Parcel, esbuild, or Gulp. These tools automate minification as part of every build, ensuring your production files are always optimized without any manual steps. This online tool is best suited for quick tasks, one-off files, or situations where a full build pipeline isn't available.
Page speed directly impacts user experience, bounce rates, and search engine rankings. Google's Core Web Vitals metrics measure loading performance, and reducing the size of your CSS and JavaScript files is one of the most effective ways to improve those scores. Even a 30% reduction in file size can meaningfully improve load times, especially for users on mobile devices or slower connections.
This tool provides instant results with no sign-up, no file size limits for typical web assets, and no data sent to any server. The compression stats give you clear, actionable information about the impact of minification on your specific files. Whether you're optimizing a personal project or preparing files for a client, this minifier gives you everything you need in a clean, distraction-free interface.
Your privacy is our priority. All processing happens entirely in your browser using JavaScript. No files, data, or inputs are ever uploaded to any server. Everything stays on your device, making this tool completely safe to use with sensitive content.