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How to reduce unused CSS

Speed1 min readFixes check unused-css

Most sites ship stylesheets where 80–90 % of the rules never apply to the page. Removing or splitting them cuts render-blocking bytes.

Step by step, with screenshots: Critical CSS: is it still worth doing in 2026? →

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What a passing site looks like

  • Little unused CSS is downloadedwarning · −4 ptseffort M

Unused CSS

Why it matters. Most of the CSS on a typical page is never used on that page. It still has to download and parse before anything renders.

How to fix it.
  1. Remove or split stylesheets so each page loads only what it needs; page builders and themes often ship one giant file.
  2. Use a "remove unused CSS" feature (WP Rocket, LiteSpeed Cache, PurgeCSS in your build).
  3. Load below-the-fold or component CSS on demand.

Filed under Speed & Core Web Vitals. Copy is generated from the same catalogue that scores every report, so what you read here is what the report says.