Definition
Core Web Vitals
Core Web Vitals are a set of Google metrics measuring real-world page loading speed, interactivity, and visual stability, used as a ranking factor in search results.
The current Core Web Vitals measure loading performance (Largest Contentful Paint), responsiveness (Interaction to Next Paint), and visual stability (Cumulative Layout Shift) — each tied to a real, user-perceptible experience rather than an abstract benchmark. Google uses these as a ranking signal, which means a slow or janky site can lose search visibility even with strong content, independent of any other SEO work.
Core Web Vitals in practice
If the main image on your service page takes 3.8 seconds to appear on a phone, your Largest Contentful Paint is 3.8 seconds, which Google rates as needing improvement. Compressing the image, serving it as WebP and loading it before less important files can bring it under the 2.5-second threshold Google rates as good.
Common questions about Core Web Vitals
What are the three Core Web Vitals?
Largest Contentful Paint (LCP) measures loading, Interaction to Next Paint (INP) measures responsiveness, and Cumulative Layout Shift (CLS) measures visual stability. INP replaced First Input Delay in March 2024.
What are good Core Web Vitals scores?
Google counts a page as good when LCP is 2.5 seconds or less, INP is 200 milliseconds or less, and CLS is 0.1 or less, measured at the 75th percentile of real visits.
How do I check my Core Web Vitals?
Use the Core Web Vitals report in Google Search Console for real-user data, and PageSpeed Insights to test individual pages and see what's slowing them down.
Do Core Web Vitals affect rankings a lot?
They're a confirmed ranking factor, but a smaller one than relevance and content quality. They matter most as a tiebreaker between similar pages, and slow pages also lose visitors before they convert.
