Starting with a great question
I just had a great Google Analytics question from one of our superstar clients and I want to share the answer with you:
What’s the difference between Page Depth and Unique Pageviews? At face value they appear to be very similar but segmenting on each shows different results. What gives?
Yes, they do seem somewhat similar. A quick Google for Page Depth shows one definition:
the average page depth is the measurement of the number of pages on your Web site that a visitor views during a single browser session.
Well that just like pages per session… How’s this different to Unique Pageviews?
We need to consult the single source of truth, the GA docs.
In reverse order, pages/session is a metric defined as:
The average number of pages viewed during a session, including repeated views of a single page.
Unique Pageviews is another metric with the definition as:
Unique Pageviews is the number of sessions during which the specified page was viewed at least once. A unique pageview is counted for each page URL + page title combination.
That’s quite different to pages/session. It doesn’t increment on repeated views of a single page and notice it combines the URL and page title to determine a page.
Finally, Page Depth. Big difference here – It’s a dimension, not a metric and is defined like so:
The number of pages visited by users during a session. The value is a histogram that counts pageviews across a range of possible values. In this calculation, all sessions will have at least one pageview, and some percentage of sessions will have more.
Page Depth is useful for asking a different question of engagement. You find the page depth report under Audience -> Behaviour -> Engagement and then choose the Page Depth tab. Notice the other tab, Session Duration is also a dimension and differs from the Avg Session Duration metric.
- “How many sessions saw x pages?”
- “How many sessions saw more than y pages?”
- “How many sessions didn’t engage?”
You might combine this dimension with average time on page and, perhaps average scroll depth if you have it, in order to start to build some form of engagement score.
There you go, hopefully that’s a bit clearer!