Core Web Vitals

Core Web Vitals are three user-experience metrics Google reports for real page loads: Largest Contentful Paint (LCP) for loading, Interaction to Next Paint (INP) for responsiveness, and Cumulative Layout Shift (CLS) for visual stability. Google’s thresholds, measured at the 75th percentile of page loads, are LCP 2.5 s or less, INP 200 ms or less and CLS 0.1 or less for “good”.

Field versus lab

The numbers that matter are field data: what real users experienced, collected through the Chrome User Experience Report and shown in Search Console and PageSpeed Insights. Lab tools such as Lighthouse simulate a load and are useful for diagnosis, but they cannot measure INP and their scores are not what Google uses.

Effect on search

Google documents Core Web Vitals as part of its page experience signals. They are not a ranking shortcut: good vitals do not lift a weak page, and poor vitals rarely sink a strong one. They matter most where two pages are otherwise similar, and they matter to users regardless.

Where to look

Search Console’s Core Web Vitals report groups URLs by status; PageSpeed Insights shows field and lab data for one URL. Our Core Web Vitals tool queries PageSpeed Insights for a URL and labels each field metric by Google’s category.