As of March 12th 2023, Interaction to Next Paint (INP) replaces First Input Delay (FID) as a Core Web Vital metric. FID and INP are measuring the same situation in the browser: how clunky does it feel when a user interacts with an element on the page? The good news for the web—and its users—is that INP provides a much better representation of real-world performance by taking every part of the interaction and rendered response into account.
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