INP (Interaction to Next Paint)

Interaction to Next Paint, acronym INP, is a metric that measures the time between when a user interacts with a page (e.g., clicking on a link or button) and when the visual response to that interaction is actually displayed on the screen.

A low INP indicates that the page responds quickly to user interactions, which is crucial for good usability and can influence user satisfaction and overall engagement with the site.

In practical terms:

• An INP value of 200 milliseconds or less means that the page has good responsiveness.
• An INP greater than 200 milliseconds and less than or equal to 500 milliseconds means that the responsiveness of the page needs to be improved.
• An INP greater than 500 milliseconds means that page responsiveness is poor.

INP is important because it provides a measure of a web page’s responsiveness and user experience by recording the latency of all interactions throughout the page’s lifecycle. This metric was introduced by Google in 2022 and will become one of the Core Web Vitals starting in 2024, replacing First Input Delay.