Google Explains How To Find Search Traffic In Analytics & Logs via @sejournal, @MattGSouthern

Google created a page on Search Central which lists the HTTP Referer values that are passed on when a user clicks to get to another website using Google Search. The page is listed as new in Google’s update log, added to document “how site owners can identify and track traffic from Google Search” within their analytics.

The same HTTP Referer values are also passed on by Discover and Google Images, the page says. That means a google.com referrer shows that Google sent someone, without showing whether they came from Search, Discover or Images.

Google Search is using the origin referrer policy, so all that appears in the header is the scheme and host of the referring page. In other words, no information about the path of the page, the query parameters and the actual search query is sent; instead, Google’s page points to Search Console’s Performance report for queries.

Google Search on the web sends either https://www.google.com/ or one of a number of local Google domains, such as https://www.google.co.uk/. Similarly, the Google app on iOS sends this. The Google app on Android sends either of these options or android-app://com.google.android.googlequicksearchbox/https/www.google.com if the app opens the link in a browser tab.

According to the webpage, Discover traffic carries the values of whichever surface it was viewed on, “such as the Google app or Google Search on the web,” and other services available through Google from the same origins, for instance Google Images, send them too.

In February 2021, Google began moving Discover traffic for Chrome to be sent via the google.com origin referrer instead of a googleapis.com referrer so that it would match Discover within the Google app.