# INP

> Interaction to Next Paint — the Core Web Vital that measures how fast a page responds to taps and clicks, replacing FID since 2024.

FID measured only the delay before the first interaction began processing; INP measures the whole response — input, processing, and the time to paint the result — across every interaction of the visit, reporting the worst-ish value. A page that feels snappy on the first click but stutters on the tenth is now measured honestly. Good is under 200ms, needs work up to 500ms, poor beyond.

The usual offenders are long tasks on the main thread: heavy JavaScript hydration, big re-renders, oversized event handlers. The fixes are the standard main-thread diet — less JavaScript, split bundles, deferred non-critical work — plus optimizing the handlers themselves: yield to paint, do work in chunks, keep the DOM small where the user actually interacts.

## Related terms

- https://dfieldsolutions.com/en/glossary/core-web-vitals.md
- https://dfieldsolutions.com/en/glossary/lcp.md
- https://dfieldsolutions.com/en/glossary/cls.md
- https://dfieldsolutions.com/en/glossary/hydration.md

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Source: https://dfieldsolutions.com/en/glossary/inp
DField Solutions — Dunakeszi, Hungary — dezso@dfieldsolutions.com
Booking: see https://dfieldsolutions.com/en/contact