INP (Interaction to Next Paint)

Sitecheck Team

A responsiveness metric measuring how quickly a page responds to user input.

INP (Interaction to Next Paint) measures the responsiveness of a page by looking at how long it takes after a user interaction for the next paint to occur. It replaced FID as a Core Web Vitals metric.

Why it matters: Poor INP indicates sluggish interactions and directly impacts how responsive a site feels.

Quick tips:

  • Reduce long tasks by splitting work and deferring non-critical scripts.
  • Optimize JavaScript execution and avoid heavy main-thread work.
  • Use passive event listeners where appropriate.

See also: Core Web Vitals, LCP, CLS.