HOW TO: Find or remove unused CSS

[Albert Wiersch]

Unfortunately, finding unused CSS across multiple pages or an entire website is not easy. It's very possible and likely to remove "unused" CSS and then to discover that there's a page or script that was using it after all.

However, CSS HTML Validator can help you find unused inline CSS classes, IDs, and type selectors. While this is just a small part of trying to remove unused CSS in an entire website, it can still be useful.

Just make sure the 'Check for unused inline classes, IDs, and type sectors' option is checked in the CSS Checker page of the Validator Engine Options. This option is enabled by default and is in the Home, Pro, and Enterprise editions.



Using Chrome DevTools, you can also view used and unused CSS with the Coverage tab.