Since the launch of Core Web Vitals in 2020, First Input Delay has been introduced, a metric that measures the responsiveness of a web page, i.e. the time it takes for the browser to respond to the user's first interaction. In particular, it measures the difference between the moment the user interacts with the device and the moment the browser can start processing event handlers.
However, this metric has limitations . FID is only measured for touches and key presses, but does not include the time spent executing those event handlers, nor any work done by the browser afterwards to update the screen.
Faced with this limitation, the Chrome team set out to azerbaijan number data seek feedback on a metric that might work better, and after a year of study, they announced the launch of Interaction to Next Paint (INP) in May 2022 , as an experimental metric .
The goal behind INP is to measure the time it takes from when a user interacts with the website until the next visual change occurs on the screen, which would allow for a broader idea of the user's actual experience and how they perceive the website's responsiveness.
Google explains: “ It’s quite possible that your website is in the 93% of sites that have good FID performance on mobile devices; however, you might be surprised to learn that only 65% of sites have a good INP on mobile devices. INP paints a much more accurate picture of responsiveness, so these numbers help us see more clearly the room for improvement that lies ahead . ”