CORE WEB VITALS & PERFORMANCE
Interaction to Next Paint: what it means and how it works
How quickly a page visibly responds to taps, clicks and typing; good is 200 ms or less.
- Advanced level
- 2 primary sources
- Reviewed 29 October 2026
- TopicCore Web Vitals & performance
- LevelAdvancedFor technical SEOs and developers
- Also calledINP
- Sources2 primary sourcesweb.dev
- Reviewed29 October 2026Re-checked every 12 months
On this page
Quick definition
Interaction to Next Paint (INP) measures how quickly a page visibly responds to clicks, taps and key presses, across the whole visit. It reports roughly the slowest interaction; 200 milliseconds or less at the 75th percentile is good. It replaced First Input Delay as a Core Web Vital in March 2024.
How it works
For each interaction, the browser measures from the user’s input to the next frame painted after the event handlers run. INP takes the longest of these for most pages; on pages with many interactions it ignores one outlier for every 50 interactions.
| Phase | What it is | Typical cause when slow |
|---|---|---|
| Input delay | Waiting before handlers can run | The main thread is busy with other scripts |
| Processing time | Running the event handlers | Heavy handlers, large re-renders |
| Presentation delay | Calculating layout and painting the next frame | Very large DOM, expensive style recalculation |
FID measured only the input delay of the first interaction. INP covers every interaction and all three phases, so many sites that passed FID fail INP.
Example
On a WooCommerce category page, tapping a filter freezes the screen for 650 ms because the theme re-renders 120 product cards and a third-party chat widget is running a long task. Showing immediate feedback, splitting the work into smaller tasks and deferring the widget until after the first interaction brings INP under 200 ms.
How to check it
- Check field INP in Search Console or PageSpeed Insights. A page-load lab test has no interactions, so it cannot report INP.
- Reproduce slow interactions with the browser’s performance panel, using CPU throttling to mimic mid-range phones.
- Look for long tasks from third-party scripts, analytics, chat and tag managers.
Common mistakes and misconceptions
Myth INP only matters for web apps.
In fact Menus, filters, accordions, add-to-cart buttons and consent banners are all interactions on ordinary sites.
Check it on your site
Free tools, no sign-up
- FreeCore Web Vitals CheckerCheck a page’s real-user LCP, INP and CLS from the Chrome UX Report, for the page and its whole site.Open the tool
- FreeJavaScript SEO Dependency CheckerSee what a crawler that does not run JavaScript gets from a page: text, title, canonical, links and structured data in the server’s HTML.Open the tool
In the NdovuSEOLabs platform
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Sources and review
- Interaction to Next Paint (INP) web.dev
- Web Vitals web.dev
Written and maintained by Ndovu SEO Labs. First published 29 October 2026. Facts last checked against the sources above on 29 October 2026. How we write and review the glossary.