Interaction to Next Paint

Interaction to Next Paint (INP) is an experimental metric that reports one of the longest delays between user interaction and the browser response throughout the entire page lifecycle.

How is Interaction to Next Paint calculated?

For Interaction to Next Paint calculation, interaction can be one of the following events:

• clicking on an interactive element with a mouse
• tapping on an interactive element with a touchscreen
• pressing a key (on physical or onscreen keyboard)

An interaction might also consist of multiple events composed of three phases: the input delay, the processing time, and the presentation delay. INP will be calculated as the visitor leaves the page.

Interaction to Next Paint represents the page’s overall latency and will also vary depending on how interactive a page (e.g. a reasonably static website versus a highly interactive application) is:

• less than 50 interactions in total: INP is the interaction with the worst latency
• more than 50 interactions in total: INP is most often in the 98th percentile of interaction latency

What Interaction to Next Paint measurement is fast?