Recently, many users have started receiving messages from Google Search Console saying that they need to fix their INP metrics in Core Web Vitals. At this point (July 2023), Google PageSpeed Insights has not made any changes and does not measure this metric in any way. Google introduced the INP (Interaction to Next Paint) metric back last year at the Google I/O conference. All we know so far is that INP is designed to measure the overall response rate to user actions on a page.
Core Web Vitals has a metric of interactivity FID (First Input Delay), but this indicator has several limitations, for example, it covers only the first interaction of the user with the site. So Google came to create a new metric INP, which takes into account the life cycle of the page completely and will be able to become an alternative to FID. During a year the new metric was tested by a community of specialists, after which Google decided to promote INP as a new indicator of Core Web Vitals, instead of the FID metric. The full replacement is scheduled to take place in March 2024.
As reported on Google’s blog, Search Console will include the INP metric in the Core Web Vitals report later this year and the FID metric will disappear from the report in 2024. Google notes that if site owners followed Google’s recommendations and improved the FID metric, those changes will have a positive impact on the INP metric as well.