Minifying your CSS files: Crawl Audit check 82

Short answer: minifying strips the comments, spaces and line breaks that make CSS readable to people but mean nothing to browsers. The file gets smaller and arrives sooner. Most modern tools do it for you. Check 82 warns when PageSpeed finds CSS that could be smaller, or, without PageSpeed, when inline CSS looks unminified.

What Crawl Audit checks

• Full report: Lighthouse's "Minify CSS" audit. A warning shows the possible saving.
• Free check: if the page has a <style> block and the HTML contains indented lines, Crawl Audit warns that inline CSS looks unminified. It's a rough test: indented HTML alone can trigger it.
• Pass: nothing to minify found.

What Google says

• Lighthouse estimates the saving "based on the comments and whitespace characters that it finds in your CSS. This is a conservative estimate."
• Lighthouse doesn't set a size threshold for this audit. Any saving it finds is listed.

On devmarde.com

PageSpeed passed "Minify CSS" for our homepage on 3 October. The stylesheet is built and minified by Next.js.

On your platform

• WordPress: many caching and performance plugins have a "minify CSS" setting. Test the site after switching it on.
• Shopify, Wix and Squarespace: the platform serves its own CSS. Check any custom CSS you've pasted in.
• Next.js and other build tools: production builds minify CSS by default.

Sources

• Chrome for Developers, Minify CSS, checked 3 October 2026.