Core Web Vitals — data sources we used

2 min readApr 19, 2021

Chrome UX Report in DataStudio

Field data.

Is powered by real user measurement aggregated from Chrome users who have opted-in to syncing their browsing history.

We set up reporting in DataStudio following these guides

https://web.dev/chrome-ux-report-data-studio-dashboard/

Pros: Real user data. Lots of data. What Google is using. Source of truth. Compare to competitors. Shows historical data.
Cons: Only monthly data. Have to wait for second Tuesday of month for previous month’s data. Can’t see breakdown of what pages contribute to which scores. Only measures Chrome users.

PageSpeed Insights

Lab data and Field data (from Chrome UX Report) Link

Can show both field and lab data for a specific URL and for all pages on the domain. (lots of pages don’t seem to have enough data).

Pros: Page-level real user data. Last 28 days.

Cons: No historical data over time

Search Console

Field data (from Chrome UX Report)

Pros: Very clear breakdown of Good vs Bad vs Needs Improvement URLs. Small list of example URLs

Cons: No breakdown of all pages and how each performs. That is left to PageSpeed Insights.

Web-vitals we collected ourselves

Field data

We used the web-vitals library to send the data to GTM and GA for real users.

Pros: Should good view of all our users and allow us to slice and dice data as we wish.

Cons: Have to set up all reporting ourselves. Took a long time to do.

Calibre or treo.sh or any other lab data provider

Lab data

Calibre (or any of the others) is a web performance monitoring tool we pay for. We’ve set it up to take Snapshots every 3 hours of variety of pages.

Pros: Gives strong breakdown of everything you’d get from Lighthouse. Pulse shows nice changes over time. Able to get almost instant feedback on changes.

Cons: Only 30 days worth of data is saved. Not real user data. Not indicative of what real numbers will be.

Lighthouse

Lab data

Can be run in chrome to get quick results.

Pros: Super fast feedback.

Cons: No historical data. Not super reliable (lots of volatility)

Web Vitals Chrome Extension