What is Core Web Vitals?
Google's three page-experience metrics — Largest Contentful Paint (LCP), Interaction to Next Paint (INP), and Cumulative Layout Shift (CLS) — that factor into search ranking.
Core Web Vitals are real-user performance metrics Google uses as a ranking signal. LCP measures how fast the largest element renders (target: under 2.5 seconds). INP measures responsiveness to user input (target: under 200ms). CLS measures unexpected layout shifts (target: under 0.1). Sites that fail these on mobile see ranking penalties. InBuild generates Next.js code with font preloading and no layout-shifting patterns by default — image optimization is not part of that (exported images render as a plain `<img>`, not `next/image`) — so Core Web Vitals start in reasonable shape but you'll want to add image optimization yourself if LCP is image-bound.