CSS Minifier Online
Minify CSS and JavaScript to reduce file size. Shows original vs minified size and % reduction. Download minified file.
Advertisement
About CSS & JavaScript Minifier Online
Minify CSS and JavaScript files by removing whitespace, comments, and unnecessary characters. Shows before/after file size and compression percentage. Download minified file directly. All processing client-side.
Minifying CSS and JavaScript before deployment — stripping whitespace, comments, and unnecessary characters without changing functionality — measurably reduces file size and improves page load time, which directly affects both user experience and Google's Core Web Vitals scoring, a factor in search ranking. While most production build tools (Webpack, Vite, etc.) handle this automatically as part of a build pipeline, there are common situations where a quick manual minify is faster — a standalone script, a quick fix to a static site without a build step, or checking exactly how much size reduction minification actually achieves on a specific file. This tool minifies CSS and JavaScript instantly in the browser and shows the before/after file size comparison.
How to use
- Paste or type your input directly into the editor — output updates in real time as you work.
- Check the error/status indicator if your input is invalid; it points to the exact line or issue where relevant.
- Use the copy or download button to grab the processed output once it looks right.
- Chain into a related tool below if your workflow needs a second processing step.
- Processing happens entirely client-side in your browser — nothing you paste is uploaded to a server.
Tool details
⚡ Next step — complete your workflow
Frequently asked questions
How much does minification reduce file size?
Typically 15-30% for CSS, 20-40% for JavaScript. Combined with Gzip compression, effective reduction is 60-80%.
Does minification affect functionality?
No, if done correctly. Minification only removes whitespace and comments. For JS, be careful with variable renaming (uglification) — test thoroughly.
Advertisement