Snowflakes are unique

I was hoping to reference “OK, Boomer”, but a snowflake seemed more appropriate.

We love Google Analytics trivia. This tidbit fits squarely in that category. The title says it all. Unique pageviews in Google Analytics are only relative to a given session, not to the user (credit Google with smushing “page” and “views” together into “pageviews”).

Where user activity is not being recorded against a User-ID enabled Google Analytics view, a “user” is really just a unique device-browser combination (notwithstanding Google Signals efforts). Generally, if I view the same page on the same device from, for example, installed Chrome and Safari browsers, I am reported as two separate users in Google Analytics.

With a non-User-ID enabled Google Analytics view, from the same browser-device combination, if I view a page in session one on day one, and the same page again in session two on day two, with a report date range that spans both days – I am reported as having two unique pageviews. The metric name “unique pageviews” betrays that reality. But, Google Analytics help content sets the record straight:

“A unique pageview, as seen in the Content Overview report, aggregates pageviews that are generated by the same user during the same session. A unique pageview represents the number of sessions during which that page was viewed one or more times.”

Live in its natural habitat

A natural habitat

How can we see this phenomenon in Google Analytics reporting? Let’s consider a popular blog post of ours, “Making Sense of Google Analytics Users, User Type and New Users“. Below we show two report snags related to activity on this page. Both add custom dimension “GA Client ID” as a secondary dimension. Client ID is the unique value assigned in the Google Analytics cookie for a unique device-browser combination.

  1. Behavior > Site Content > All Pages. Here we can see for a week date range that the same “GA Client ID” has 3 unique pageviews for the same page. Huh? Yes, that’s exactly what the above help content says will happen. Why? See item 2.
  2. Acquisition > All Traffic > Source / Medium. Here we see the same week date range, with the same “GA Client ID” value, that there were three sessions engaged by this “user”. It follows then, if the user viewed the page in item 1 in each of their three sessions, they are reported as having three unique pageviews, not one unique pageview as the metric name would insinuate.

Now you know!

1. 11/12/19 – 11/18/19 (UA-370679-1)
GA Page, with Client ID, showing Unique Pageviews
2. 11/12/19 – 11/18/19 (UA-370679-1)
Source / Medium, with Client ID, showing Sessions
Google Analytics unique pageviews do not span multiple sessions