Overview
INP is the successor to First Input Delay (FID). While FID only measured the very first interaction, INP observes all interactions (clicks, taps, and keyboard presses) and reports the longest duration, providing a more comprehensive picture of a page's responsiveness.
How it is Calculated
INP measures the time from the start of a user interaction until the next frame is painted on the screen. This includes the input delay, the processing time of event handlers, and the presentation delay.
Targets
- Good: Under 200 milliseconds.
- Needs Improvement: Between 200 and 500 milliseconds.
- Poor: Over 500 milliseconds.
Importance
As a Core Web Vital, INP directly impacts search engine rankings and is a key indicator of a high-quality user experience.