Lighthouse Best Practices score
The Best Practices score, from 0 to 100, sums up a set of technical checks in Lighthouse: is the page delivered securely over HTTPS, does it write errors to the browser console, does it use browser features that are being phased out, are images shown in the right proportions?
Why it matters
Section titled “Why it matters”These checks catch problems visitors rarely see directly but do feel: a browser warning about an insecure connection, a feature that stops working in the next Chrome version, a blurry or squashed image. They also hint at code that needs attention before it breaks.
The score isn’t a security audit. It checks a handful of things on one page from the outside and says nothing about how well the WordPress installation itself is protected. Some checks in the report, such as those for security headers or known vulnerable JavaScript libraries, are listed for information and don’t count toward the score.
What influences it
Section titled “What influences it”WordPress: On WordPress sites, the most frequent causes are embedded content and scripts from other services: videos, maps, social media feeds, ads and tracking. They set third-party cookies or rely on browser features that are being phased out, two of the checks that weigh most, and they often log errors to the console. Themes and plugins that haven’t been updated in a long time cause the same problems with their own scripts.
Network: A page served over plain http, or one that loads single images or scripts
over http on an https page, fails the checks for secure delivery.
Server: A server that doesn’t redirect http requests to https fails another
check in the same group.
Browser: Images displayed in different proportions than the original, or at a lower resolution than the screen needs, fail the image checks.
In Permo
Section titled “In Permo”Permo shows the Best Practices score as a small ring under Other categories on its PageSpeed page, from the same test as the Performance score. Its trend arrow appears from a change of 1 point, because this score only changes when the page changes.