Metrics
Interaction to Next Paint (INP)
Also: INP
Worst-case latency between a user input and the next visual update.
Definition
A Core Web Vital that replaced First Input Delay in March 2024. Measures the longest interaction (click, tap, key) latency through the session. Good < 200ms, needs improvement 200-500ms, poor > 500ms. Heavy JS event handlers, large React re-renders, and main-thread work hurt INP.
See also
More in Metrics
Largest Contentful Paint (LCP)
The render time of the largest content element visible in the viewport.
Cumulative Layout Shift (CLS)
How much visible content unexpectedly shifts during a page lifetime.
Time to First Byte (TTFB)
The time between request and the first byte of response from the origin or CDN.
Time to Interactive (TTI)
The time until the main thread is reliably free to handle user input.
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