Core Web Vitals are the speed metrics that are part of Google’s Page Experience signals used to measure user experience. The metrics measure visual load with Largest Contentful Paint (LCP), visual stability with Cumulative Layout Shift (CLS), and interactivity with First Input Delay (FID).
The easiest way to see the metrics for your site is with the Core Web Vitals report in Google Search Console. With the report, you can easily see if your pages are categorized as “poor URLs,” “URLs need improvement,” or “good URLs.”
Quick facts about Core Web Vitals
Fact 1: The metrics are split between desktop and mobile, but only mobile signals will be used for ranking pages. Google is switching to 100% mobile-first indexing in March, so it makes sense to use the mobile speed signals since the indexed pages will also be based on the mobile versions.
Fact 2: The data comes from the Chrome User Experience Report (CrUX), which records data from opted-in Chrome users. The metrics will be assessed at the 75th percentile of users, so if 70% of your users are in the “good” category and 5% are in the “need improvement” category, then your page is still judged as “need improvement.”
Fact 3: The metrics will be assessed for each page, but if there isn’t enough data, John Mueller states that signals from sections of a site or the overall website may be used.
Fact 4: With the addition of these new metrics, AMP is being removed as a requirement from the Top Stories feature on mobile. Since new stor