In March 2024, Google replaced First Input Delay (FID) with Interaction to Next Paint (INP) as a Core Web Vital. If you have not audited your INP score, do it now.
What Is INP?
INP measures the latency of ALL interactions on your page — clicks, taps, key presses. Target: under 200ms (Good), 200-500ms (Needs Improvement), 500ms+ (Poor).
Common INP Problems
- Heavy JavaScript blocking the main thread
- Synchronous API calls on user interaction
- React state updates triggering expensive re-renders
- Third-party scripts blocking interaction response
Quick Wins
Defer non-critical JavaScript. Break long tasks into smaller async chunks. Remove or defer third-party scripts that block the main thread.
