Matan · Performance · Core Web Vitals
Field LCP (CrUX) (Performance)
Google ranks on real-user Largest Contentful Paint at the 75th percentile, not on a single Lighthouse run.
Pass condition in our engine: CrUX p75 LCP is under 2.5s when field data exists; otherwise the HTML LCP-risk checks pass.
This Performance check is part of SEO-GEO scoring 2.2.1, last updated 2026-09-18. About 90 percent of the evaluation runs on the HTML we crawl, so you can verify the same pass condition with a free report.
1. Problem description
Lab LCP is a diagnosis tool. Search uses Chrome User Experience Report data over 28 days. A page “passes” when p75 is under 2.5s.
2. Most common causes
- Slow TTFB or a CDN-less origin.
- Hero image discovered late (lazy-loaded or injected by JS).
- Render-blocking CSS/JS delaying first paint of the LCP element.
3. How to fix it
- Preload the LCP image with fetchpriority=high.
- Serve AVIF/WebP from a nearby edge.
- Fix TTFB first — every millisecond of server delay is added to LCP.
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