How do you optimize interactions to lower your INP value?

Short answer: Lowering INP means optimizing the three parts of your slowest interaction separately (input delay, processing time, presentation delay); the goal is staying under Google's published 200 millisecond threshold.

Order of work

• Diagnose: find the worst interactions in field data (send web-vitals events to GA4), then reproduce the same interaction in a Chrome DevTools performance trace.
• Input delay: break up long tasks, chunk heavy work with scheduler.yield or requestIdleCallback, defer nonessential third-party scripts.
• Processing: slim down event listeners, move expensive computation to a web worker, debounce inputs.
• Presentation: shrink large DOM updates, separate the reads and writes that cause layout thrashing, use CSS containment.

Fast visual feedback also fixes perception: show a state change right after the tap and finish the heavy work afterwards. Always validate at the 75th percentile of field data; an interaction that feels quick on a strong device can blow the budget on a mid-range Android.