Answer
What is INP (Interaction to Next Paint)?
Last reviewed · WebVitalist
Interaction to Next Paint (INP) measures responsiveness: the time from a click, tap, or keypress until the page next visually updates. Google classes INP as good at 200 milliseconds or less and poor above 500 milliseconds, at the 75th percentile of field data. INP replaced First Input Delay (FID) in March 2024.
What to do about it
- Read your INP in the field data section of Google PageSpeed Insights. If your site has little traffic and no field data, use lab Total Blocking Time as a rough proxy.
- Inventory every third-party script: chat widgets, analytics, ad pixels, pop-up tools. Each one adds JavaScript that can block interaction. Remove what you do not use.
- Ask your developer to break up long JavaScript tasks and defer scripts that are not needed for the first interaction.
- Test on a mid-range phone. Field data comes from real Chrome users, most of them on mobile, not from your laptop.
- Re-measure after changes. Field data reflects a rolling window of recent visits, so improvements show up as new people visit.
What WebVitalist checks
The free scan runs 19 technical checks on one public URL. These are the ones that matter for this question:
- HTML size (html-size): The free scan warns when the HTML document is larger than 400 kB, which the browser must download and parse before it can paint anything.
- Server response time (ttfb): The free scan records how long the server took to deliver the HTML and warns when that took longer than 1,500 ms.
A paid audit ($9 and up) also runs a real mobile Lighthouse test through Google PageSpeed Insights and reads field data for LCP, INP and CLS, where Google has it.
Free scan
Paste your page URL and see the technical score and top issues in about 30 seconds. No account, no credit card.