Performance

INP

aka Interaction to Next Paint

INP measures the responsiveness of a page — the time from a user input (click, tap, key) to the next visual update the browser commits.

INP replaced First Input Delay as a Core Web Vital in March 2024. Unlike FID, INP samples *every* interaction on the page and reports a high-percentile worst case, so a single janky click sequence shows up.

Google's thresholds are 200 ms for Good and 500 ms for Poor. A common ifySEO target is tighter (≤ 150 ms) because INP is the metric most likely to regress as JavaScript bundles grow.

Most fixes involve breaking up long tasks: chunk expensive React renders with useDeferredValue or useTransition, ship less JavaScript on the first interaction, and avoid synchronous third-party scripts. A page with no third-party tags rarely has an INP problem.

Scan for this

See how your page handles inp.

Drop in any public URL. ifySEO renders the page in a real headless browser and tells you exactly what's wrong — including issues in the performance category.