How Google Analytics 4 counts sessions
- A session starts when a visitor opens a page or screen and no session is already active.
- By default it ends after 30 minutes without activity. The timeout can be changed.
- Unlike Universal Analytics, GA4 doesn’t start a new session at midnight or when the traffic source changes.
Sessions, users and page views
One user can have several sessions, and one session can include many page views. So a report may show 1,000 users, 1,400 sessions and 3,200 views for the same period.
Engaged sessions
GA4 also reports engaged sessions: sessions that lasted longer than 10 seconds, included a key event or had at least two page views. Engagement rate is engaged sessions divided by all sessions.
Sessions example
A visitor arrives from Google, reads two pages, leaves for 40 minutes and then returns directly. In GA4 this counts as two sessions by the same user, because the 30-minute timeout passed. The first session has two page views and the second has one. If the visitor had come back after ten minutes, it would still be the first session.
How to use session data
- Compare sessions by channel in the Traffic acquisition report.
- Look at engaged sessions and engagement rate, not only the total.
- Check sessions by landing page for the pages that attract visitors.
- Calculate conversions per session for each channel.
- Exclude internal traffic and bots, so that the numbers reflect real visitors.
Sessions mistakes
- Mixing up sessions, users and page views.
- Comparing GA4 sessions with Universal Analytics sessions, which were counted differently.
- Treating a rise in sessions as success, when conversions fall.
Sessions FAQs
What is the difference between a session and a user?
A user is a person or device. A session is one visit. See unique visitors and Google Analytics.
What is an engaged session?
One that lasts more than 10 seconds, has a conversion or has two or more page views. See engagement rate and bounce rate.