Suggest an editImprove this articleRefine the answer for “What does Web Vitals do?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)**Web Vitals** is a set of key metrics from Google that measure the quality of user experience on a site: how fast, stable, and responsive the page is from a real user's point of view. **Key point:** Web Vitals is the minimal required set of metrics by which Google (and the user) judges how fast, responsive, and non-frustrating a site is.Shown above the full answer for quick recall.Answer (EN)Image**Web Vitals** is a set of key metrics from Google that measure the quality of user experience on a site. They show how fast, stable, and responsive the page is from a real user's point of view. --- ### Main Web Vitals metrics: 1. **LCP (Largest Contentful Paint)** - when the largest visible element loads - reflects: how fast the main content renders - norm: < 2.5 sec 2. **FID (First Input Delay)** - the delay between the user's first action and the page's response - reflects: interface responsiveness - norm: < 100 ms 3. **CLS (Cumulative Layout Shift)** - the sum of all unexpected element shifts during loading - reflects: visual stability - norm: < 0.1 --- ### Additional (extended) metrics: - **FCP (First Contentful Paint)**: when the first content appears - **TTFB (Time To First Byte)**: when the first byte of the server response arrives - **INP (Interaction to Next Paint)**: a replacement for FID with more precise interaction measurement --- ### What Web Vitals does in practice: - **Measures** key UX metrics on real devices (via the browser) - **Sends** them to analytics (for example, to Google Analytics, BigQuery, and so on) - **Helps** identify where the site actually slows down, not just in synthetic tests - **Serves** as the basis for scoring in Lighthouse, PageSpeed Insights, and the Chrome UX Report (CrUX) --- **Conclusion:** Web Vitals is the minimal required set of metrics by which Google (and the user) judges how fast, responsive, and non-frustrating a site is.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.