LCP

Largest Contentful Paint (LCP) is a Core Web Vital metric that measures the time from when a page starts loading to when the largest visible content element (typically a hero image or heading) is rendered on screen.

Google considers an LCP of under 2.5 seconds good, 2.5 to 4 seconds needs improvement, and over 4 seconds poor. Common causes of slow LCP include large unoptimised images, slow server response times, render-blocking CSS or JavaScript, and missing preload hints for critical resources.