What is LCP (Largest Contentful Paint)?
A Core Web Vital measuring when the largest visible element on a page finishes rendering. Target: under 2.5 seconds for a 'good' score.
Largest Contentful Paint (LCP) is one of three Core Web Vitals — Google's user-experience ranking signals. It measures the time from navigation start until the largest visible element (typically the hero image, a big block of text, or a video poster) finishes painting on screen. Google's thresholds: Good ≤ 2.5s, Needs Improvement 2.5–4s, Poor > 4s. The 75th percentile of real-user data over a 28-day window is what Search Console reports. Common LCP killers: oversized hero images (always set `width`/`height` and use modern formats like AVIF/WebP), render-blocking JavaScript, slow server response times. Fixes: preload the LCP element, defer non-critical CSS/JS, host on a CDN, optimize the largest image to under 100KB.