You have probably seen something about Referral traffic show up in a bunch of places in your Google Analytics, whether you are still using the older version – Universal Analytics
or the new version, Google Analytics 4 (GA4):
Referral traffic is made up of users who are coming your website from other websites, if the links that they clicked do not have any campaign tracking information attached to them.
The other website referred those users to you, hence the name.
Referral Traffic has the value
referral in the Medium dimension which Google Analytics sets automatically whenever it detects referral traffic.
Google Analytics automatically reads this variable and will use it as a traffic source if no other information is available.
These days, the referrer is usually limited to just the domain of the referring website. That means you won’t see the entire URL of the page your users visited before to give them a little more privacy:
- User visits otherwebsite.com/super-embarrassing-topic-article
- User clicks link from there to yourwebsite.com and arrives on your site.
document.referreris automatically set by the browser to
- Your Google Analytics reads this information and will track the user with
otherwebsite.com / referralin the “Source / Medium” dimension.
Campaign information overrides the referrer
Google Analytics will ignore the referrer, if it sees better (i. e. more accurate and deliberately provided) traffic source information:
That’s the case if the link URL on the referring website contains campaign parameters such as
utm_medium and others.
Let’s assume otherwebsite.com links to your website with this URL, because you have a profit-sharing deal with them:
document.referrer variable will still contain
yourwebsite.com, but Google Analytics will ignore it in favor of the more specific information that was deliberately provided in the
Therefore, the traffic would then show up with the presumably more insightful Source / Medium combination
special-offer / affiliate.
Organic Search traffic
If you’re good at SEO, users come to your site from Google and click on the unpaid (“organic”) search results to your site.
Technically speaking, that is simply referral traffic from google.com that would usually be tracked as
google.com / referral.
But for this specific combination, Google Analytics has a built-in mechanism to change this attribution to
google / organic.
Debugging & the behind the scenes
Checking the current referrer
If you want to find out which referrer your browser is currently providing through the
document.referrer variable, you can
- Hit Enter
Check which referrer is sent to GA
When in doubt, it can help to double-check what referrer information is actually sent to Google Analytics.
The parameter responsible for this is
dr (“document referrer”).
- Open Chrome’s Developer Tools with its ‘Network’ tab
- Reload the page if they’re empty
- Filter the requests for
collectand find the requests going out to Google Analytics
- Check the requests for the
The parameter value might look a little weird with
% characters in it, that’s perfectly normal. You paste it into https://www.urldecoder.org/ and decode it to make it easier to read.