Traffic
Pages per session
Also called pages per visit, depth.
Pages per session is the average number of pageviews in a session. It is a rough depth measure.
How it is measured
Divide total pageviews by total sessions for the period. A session with one page counts as one. A single very deep session lifts the mean for everyone else.
Tarsier counts a client-side route change as a pageview, so a single-page app is not stuck at 1.0 as long as the history hook is firing. Check one in-app click after any router change.
Worked example
A knowledge-base site has 20,000 sessions and 46,000 pageviews, so 2.3 pages per session. A search-driven landing page shows 1.2 and an onboarding guide shows 4.8.
The team adds a sidebar to the one-answer pages and the number rises to 1.7, but customer satisfaction stays the same. The extra clicks were not what people wanted.
How it differs
Pages per session measures depth. Bounce rate measures single-page share. Pageview is the unit being counted. A site can lift the number by adding clicks and not improve anything, so pair it with a conversion measure.
Common errors
Treating more pages as better. Forgetting tracked routes in an SPA. Letting infinite scroll or pagination inflate it. Mixing mobile and desktop. Reading a mean without the median.
In practice
Check it per landing page and use it on content meant to lead somewhere, such as courses or catalogues. For answer pages, a low number can be a success.