What is INP (Interaction to Next Paint)?
How long the page takes to visually respond to a user interaction (tap, click, keypress). Replaced FID as the official Core Web Vitals responsiveness metric in March 2024.
Also known as: Interaction to Next Paint, responsiveness metric
INP measures the responsiveness of a page across the full session — the longest delay between any user input and the next visible paint. Where FID only measured the first interaction, INP measures all of them and reports the worst.
A good INP is under 200 milliseconds. 'Needs improvement' is 200-500ms; 'poor' is over 500ms. The biggest INP-killers are heavy JavaScript on the main thread, especially third-party scripts (chat widgets, analytics, ads) that hijack the renderer when users try to scroll or tap.
Fixing INP means: defer non-critical scripts, code-split large JavaScript bundles, avoid long-running tasks on the main thread, and audit any third-party widget that runs on every page. Nexora ships sites with median INP under 100ms by being aggressive about what gets shipped to the client at all.
Slow INP makes a site feel laggy — taps don't respond, scrolling stutters. It's the metric most directly tied to perceived quality.
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