INP explained: making every interaction feel instant

Interaction to Next Paint measures how quickly your page responds to every click, tap and keypress — not just the first.

What is a good INP?

Under 200 ms at the 75th percentile. Our sites target under 50 ms.

Common culprits

• Long tasks from heavy third-party scripts
• Large React re-renders triggered by a single state change
• Synchronous layout work inside event handlers

Fixes that work

Break up long tasks, defer non-critical work with requestIdleCallback, keep state local and use CSS for animations wherever possible.