Interaction to Next Paint (INP)
Design Processes
How quickly the page responds when you tap or click.
In practice
Interaction to Next Paint measures the delay between a user's input — a tap, a click, a key press — and the next time the screen visually updates in response, across the whole visit, reporting one of the worst. It replaced First Input Delay because a page can be fast to first tap and sluggish thereafter. Heavy JavaScript on the main thread is the usual culprit.
Questions
What is Interaction to Next Paint (INP)?
INP is the latency from a user interaction to the next frame the browser paints, taken as a near-worst case over the visit.
Why do you use Interaction to Next Paint (INP)?
Slow response is the difference between an interface that feels solid and one that feels stuck. Google wants under 200 milliseconds.
How do you use/apply Interaction to Next Paint (INP)?
Cut main-thread work: split and defer JavaScript, avoid long tasks, yield during heavy updates, and keep event handlers light.
When do you use Interaction to Next Paint (INP)?
On any interactive page, and especially after adding scripts, animation libraries or analytics.
Who uses Interaction to Next Paint (INP)?
Front-end developers, and designers specifying interactions that must feel instant.
