Core Web Vital measuring page responsiveness — the delay between user interaction and visual response on screen.
Interaction to Next Paint (INP) measures the responsiveness of a web page by tracking the time between a user interaction and the next visual update on screen. As Google's newest Core Web Vital replacing First Input Delay in March 2024, INP captures the full lifecycle of user interactions — from the initial input through event processing to the browser painting the response.
Unlike First Input Delay which only measured the delay before processing begins, INP provides a comprehensive view of interaction responsiveness. It considers all user interactions during a page visit and reports the worst (or near-worst) interaction latency, making it a more accurate reflection of user experience.
Why It Matters for AI SEO
INP has become critical for SEO success as Google integrates page experience signals more deeply into ranking algorithms. Modern AI-powered websites often feature dynamic content, real-time personalization, and interactive elements that can significantly impact INP scores. Heavy JavaScript execution from AI chatbots, recommendation engines, or content personalization systems can create interaction delays that hurt both user experience and search rankings. AI tools that generate dynamic content or provide real-time interactions must be optimized for responsiveness. Poor INP scores can signal to Google that your AI-enhanced user experience is actually degrading site performance, potentially offsetting any content quality benefits from AI implementation.
How It Works
INP measures three phases of interaction: input delay (time to start processing), processing time (executing event handlers), and presentation delay (rendering the visual response). A good INP score is under 200 milliseconds, while anything over 500ms is considered poor. To optimize INP, focus on reducing JavaScript execution time during interactions. This means breaking up long tasks, using web workers for heavy processing, and implementing efficient event handlers. For AI-powered features, consider lazy loading AI components, caching AI responses, and using streaming responses to provide immediate feedback. Tools like PageSpeed Insights and GTmetrix now provide INP diagnostics, while Google Search Console flags INP issues in its Core Web Vitals report. Practical optimization includes debouncing frequent interactions, optimizing third-party scripts (including AI widgets), and ensuring your AI-generated content doesn't block the main thread during user interactions.
Common Mistakes
The biggest mistake is assuming INP only affects interactive elements like buttons or forms. In reality, any user interaction — including scrolling, hovering, or typing — can trigger INP measurement. Many sites implement AI features that perform heavy computations on every interaction without considering the cumulative impact on responsiveness. Another common error is optimizing only for First Input Delay without addressing the full interaction cycle. Sites may quickly acknowledge user input but fail to provide timely visual feedback, resulting in poor INP scores despite good FID performance.