Google PageSpeed Insights Adds Partial Field Data

Google has upgraded the Google PageSpeed Insights tool to show partial field data. Google said "previously, field data was only surfaced if all metrics for a page or origin met a threshold of data." "Now, any metric that meets the data threshold will be provided," Google said.

Rick Viscomi, Senior DevRel Engineer at Google, said on Twitter "Previously you'd see "no data" if you were just missing FID data. Now you'll see whatever is available. This is a big deal because ~30% of origins in CrUX were missing FID data!."

He also added these tweets:

How does this affect the Core Web Vitals assessment? If FID is present, it needs to be good in order to pass. If FID is missing, the page/origin is assessed by its LCP and CLS alone.

LCP and CLS are required to be present for CWV to be assessed.

— Rick Viscomi (@rick_viscomi) June 10, 2021

This is reflected in the loadingExperience and originLoadingExperience objects in the API, and also in the frontend.

So now you can see a bit more data when previously you may have not been able to see it.

Forum discussion at Twitter.