Largest Contentful Paint (LCP)
A Core Web Vital measuring the render time of the largest above-the-fold element — usually a hero image, video poster, or headline block. Target: 2.5 seconds or less at the 75th percentile.
LCP captures the moment the user perceives the page as rendered.
Pre-loading the hero image with <link rel="preload"> and
fetchpriority="high", serving modern image formats, removing
render-blocking resources, and inlining critical CSS are the four
levers most production deploys use. Median improvement from
fetchpriority="high" on the LCP image alone is about 0.5 s on
real-world sites.