web-vitals-inp-deep

INP is "the time from the start of the interaction to the moment the next frame is fully presented" per the [INP web.dev article]. Thresholds at the 75th percentile of page loads:

• Good: ≤ 200 ms
• Needs Improvement: 201 - 500 ms
• Poor: > 500 ms

When to use

• A page reports "feels slow" but LCP and CLS are green - INP is the missing dimension.
• Pre-merge gate: assert key user interactions (form submit, modal open, route transition) stay under budget.
• Field debugging: correlate field INP outliers with specific interaction types.