Enable Core Web Vitals
When setting up a new crawl or within the project settings for an existing crawl, you can now enable Core Web Vitals to get page speed data for your pages.
You’ll need to get a free API key from Google and then enter the code in the box.
Click the “Get a Key” button and follow the steps.
You’ll receive your own API key which you will need to copy and enter into your project settings under the CWV section.
We’ll verify the key you enter and if everything looks good you should see a notice with a green check mark that says Valid, or we’ll show an error and a Retry button if there’s a problem.
Save your settings and you’ll get CWV data the next time you run a crawl. I’ll reiterate, you need to run a new crawl after you save your settings to get this data. If you change the settings while a crawl is already running, you will not get the data.
Note that the data you get will depend on whether you have selected the desktop or mobile version for the crawler. If you want mobile CWV data, make sure to select the mobile AhrefsSiteAudit user-agent.
Where to find the metrics
In Site Audit, you’ll want to go to Page explorer and click “Manage columns.”
Select the metrics you want to see and click Apply. If you click the box for “Core Web Vitals” it will select all the metrics.
This will add the selected columns to Page explorer for you to view or export. We retrieve some fields related to Lighthouse (lab data) and others for Core Web Vitals (field data). The full list includes:
PSI API status
PSI API error message
CrUX CLS category
CrUX FID (ms)
CrUX FID category
CrUX LCP (sec)
CrUX LCP category
CrUX CLS distribution
CrUX FID distribution
CrUX LCP distribution
Lighthouse Performance score
Lighthouse CLS error message
Lighthouse TBT (ms)
Lighthouse TBT error message
Lighthouse LCP (sec)
Lighthouse LCP error message
You can hover over any of the metrics to show tooltips with more details and also refer to our article on CWV for more information.
Some data may be missing from the reports. There are a few reasons for this including:
An error with the API request. Check the “PSI API status” and “PSI API error message” columns to see the reasons.
CWV numbers may not be available for all pages. Less popular pages may have no data or only partial data in CrUX (Chrome User Experience Report) which is the source of CWV data and comes from users of Chrome who opted to share data.
We’ll add some pretty charts in the future to make this part easier for everyone.
About the API quotas
Because we’re pulling data from the connected PageSpeed Insights API, your account is subject to a couple of limits put in place by Google. At the time of writing these are the current limits put in place:
You can use the PageSpeed Insights API dashboard to monitor your usage.
Ahrefs will stay within the default queries per minute limit, but on larger sites you may exceed the queries per day limit. If this happens, you have a couple options.
You can schedule smaller crawls on different days to get the data you need.
If you are exceeding your quota, you can request higher limits.