What is INP (Interaction to Next Paint)?
INP (Interaction to Next Paint) is a metric designed to measure how long it takes for a web page to respond to a user interaction (clicks, taps).
More About INP (Interaction to Next Paint)
INP to Replace FID (First Input Delay)
Google’s Chrome Team announced in May 2023 that INP will be replacing FID (First Input Delay) in 2024. Interaction to Next Paint (INP) is currently being positioned as a replacement for First Input Delay (FID) as a primary core web vitals metric. INP will provide more accurate results and better real-world performance, and be the preferred metric going forward in measuring webpage responsiveness after user interaction.
How is INP Measured?
A low INP score means there is little latency between a user interaction and a response, whereas a high INP score indicates increased latency between user interaction and response. According to Google:
- An INP below or at 200 milliseconds means that your page has good responsiveness.
- An INP above 200 milliseconds and below or at 500 milliseconds means that your page’s responsiveness needs improvement.
- An INP above 500 milliseconds means that your page has poor responsiveness.
Why is INP Better Than FID?
The entire idea behind deploying the INP metric was to try to capture broader end-to-end latency of an event. Since First Input Delay only captured a portion of the latency between the moment a user clicked and the browser completed responding, the reading was, for lack of a better term, inaccurate.
The Google Chrome teams aims to position INP as a complete measure of a web page’s responsiveness after user interaction.