CSS Minifier

Typically 20–40 % before gzip: a hand-written 40 KB stylesheet with comments and indentation becomes 25–30 KB. After the server’s gzip or Brotli compression the difference shrinks to a few percent, because compression already removes repetitive whitespace — minifying still helps parse time and is free.

Yes. The minifier only removes things browsers ignore — comments, whitespace, the final semicolon in a block — and applies two lossless shorthands (0.5 → .5, #aabbcc → #abc). It never merges rules, reorders declarations or drops anything, so specificity and behaviour are unchanged.

For a site with a build step (Next.js, Vite, webpack, Tailwind) minification is automatic — use this tool for one-off files: a WordPress child theme, an email template, a Shopify section or inline critical CSS. Keep the unminified source in version control and minify the copy you deploy.

No — all comments are removed, including license headers. Re-add a license comment at the top of the minified file if the stylesheet’s license requires it.

No. Minification is a few regular expressions running in your browser.