CSS/HTML/JS Minifier

Free CSS/HTML/JS Minifier

Minify CSS, HTML and JavaScript code to reduce file size. Removes comments, whitespace and unnecessary characters. Shows size reduction percentage.

Paste CSS, HTML, or JavaScript code into the input field and click Minify to remove all unnecessary characters. The tool strips comments, whitespace, and line breaks while preserving functionality. For CSS, it consolidates properties and removes redundant semicolons. For JavaScript, it removes whitespace outside strings and combines statements where safe. For HTML, it collapses whitespace between tags. The output displays the minified code and shows the size reduction as both bytes saved and percentage. Copy the minified output for use in production. All processing happens in your browser.

Frontend developers minify CSS and JavaScript before deploying to production, reducing file sizes to improve page load times. Web performance engineers optimize sites by minifying all assets, seeing immediate size reductions of 30-60 percent. Build pipeline maintainers test minification tools by comparing output sizes and verifying functionality remains intact. Site auditors identify unminified assets that should be optimized by checking production source code.

Minify during your build process rather than manually to ensure you don't accidentally edit minified code, which is extremely hard to debug. Keep source maps for JavaScript minification so browser dev tools can show original code during debugging. Test minified code in a staging environment before deploying; aggressive minification can occasionally break code with unusual syntax. Combine minification with gzip compression for maximum benefit; minified files compress better since they have less variability. For production builds, use dedicated tools like Terser for JavaScript or cssnano for CSS, which apply more aggressive optimizations than this simple browser-based tool.

All processing happens directly in your browser. Your files never leave your device — no server uploads, no cloud storage, no data retention. The tool works offline once loaded, requires no registration, and is completely free with no usage limits.