INP (Interaction to Next Paint).
INP is the newest Core Web Vital from Google and measures the responsiveness of a website: How quickly does the page react to user interactions (clicks, taps, keyboard inputs)? INP has replaced FID (First Input Delay) as a metric.
INP (Interaction to Next Paint) — Explained in Detail
INP (Interaction to Next Paint) has been the official Core Web Vital for interactivity since March 2024 — replacing FID (First Input Delay). INP measures the time from a user interaction (click, tap, keyboard input) to the next visual update (paint) on the screen. An INP below 200ms is considered 'good', 200–500ms as 'needs improvement', and above 500ms as 'poor'. Unlike FID, which only measured the first interaction, INP considers all interactions throughout the entire session.
Why was FID replaced by INP? FID only measured the delay until the processing of the first input — not the total time until visual feedback. A page could have a good FID but still respond slowly to clicks if the event handler or rendering was slow. INP captures the complete chain: Input Delay + Processing Time + Presentation Delay. It is a more comprehensive measure of the 'perceived speed' of a website.
Common INP problems and solutions: Heavy JavaScript execution blocks the main thread (solution: code splitting, Web Workers, script deferring), slow event handlers (solution: debouncing, asynchronous processing), complex re-rendering (solution: virtual scrolling, CSS containment, React.memo). DLM Digital systematically optimizes INP in all web projects — modern React architectures with code splitting routinely achieve INP values below 100ms.
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Premium WebsitesFrequently Asked Questions About INP (Interaction to Next Paint)
Field data (real users): Google Search Console > Core Web Vitals Report, Google PageSpeed Insights (CrUX data), Chrome User Experience Report (CrUX). Lab data (synthetic measurement): Chrome DevTools > Performance Tab (shows 'Total Blocking Time' as a proxy), WebPageTest. Important: INP is a field metric — it is calculated from real user data. Lab data may differ.
Below 200ms is considered 'good' (green). 200–500ms as 'needs improvement' (yellow). Above 500ms as 'poor' (red). For optimal user experience and SEO, you should stay below 200ms. For comparison: The majority of WordPress websites have INP values of 300–800ms. Modern React/Next.js websites with optimized code achieve 50–150ms.
Yes. INP has been an official Core Web Vital since March 2024 and is therefore a direct Google ranking factor — it replaced FID (First Input Delay). Along with LCP (Largest Contentful Paint) and CLS (Cumulative Layout Shift), INP forms the third pillar of the Core Web Vitals. Websites with poor INP can be disadvantaged in mobile rankings — especially when content quality is comparable.
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