FID (First Input Delay)

FID (First Input Delay) is a measure of the time frame between when an input is received from the user and when the final screen responding to that input is shown. It was one of the three core web vitals, including LCP, FID, and CLS, until March 2024. On March 12, Google replaced FID with INP (Interaction to Next Paint), which is the new official core web vital metric.

FID is an important indicator of how responsive a website is for its users and how well the user experience it delivers. Here, First Input refers to the first interaction a user makes with a website, such as a click, a tap, or anything else.

FID measures the time between when the user interacts with a web page for the first time and when the page finally responds to that interaction. A higher FID means poor responsiveness. The more a web page takes to respond to an interaction, the poorer its responsiveness. 

An FID score of less than 100 milliseconds is considered ideal for a web page. Let us understand how you can determine a page’s responsiveness using FID scores:

• An FID score of up to 100 milliseconds is considered ‘good.’
• An FID score of 100 to 300 milliseconds denotes that your website ‘needs improvement.’
• An FID score above 300 milliseconds is considered ‘poor.’

A delay in first interaction leads to frustration in the users and they tend to leave your website before it responds. This is why optimizing for FID is quite important. 

As now FID has been replaced by INP in Google’s core web vital system, website owners should also shift their focus accordingly. FID doesn’t capture interactivity in many ways, which INP does. Therefore, INP becomes a more relevant metric to measure the responsiveness of your web pages. FID has also been removed from the Google Search Console report now and you will instead see INP scores there.