What is a session in web analytics?

What a session is

Analytics tools record individual hits — a pageview, a click, a purchase. A session groups those hits into visits. Everything a visitor does from the moment they arrive until they go quiet for longer than the timeout belongs to one session.

Sessions exist so you can answer visit-level questions: how long a visit lasts, how many pages people see per visit, which page a visit started on, and which campaign brought it. Without sessions you only have totals.

A worked example

A visitor arrives from a search result at 9:00, reads two pages, leaves the tab open and comes back at 9:20 to view pricing. That is one session with three pageviews, because the gap of 20 minutes is under the 30-minute timeout.

The same visitor returns at 10:15 from a newsletter link. More than 30 minutes have passed, so this is a second session — and its source is the newsletter, not the search engine. Session-level reports will show one search session and one email session.

Why session counts differ between tools

Every tool uses an inactivity timeout, but the rest of the rules vary:

• Timeout length. 30 minutes is the common default. Google Analytics 4 lets you raise it up to 7 hours 55 minutes.
• Midnight. Universal Analytics ended every session at midnight; GA4 does not.
• Campaign changes. Universal Analytics started a new session when the same visitor arrived with new campaign parameters; GA4 does not.
• Sign-in. Some tools end a session when a different user signs in on the same device.
• Visitor identity. If the tool cannot recognise a returning visitor — cleared cookies, a new device — the hits start a new visitor and a new session.

A difference of a few percent between two tools is normal. A difference of 30% or more almost always means one of them is missing pages or counting bots.

How TapCub splits sessions

TapCub closes a session after 30 minutes of inactivity by default and caps a single session at 24 hours; both limits can be changed. A session also ends when the signed-in user on the device changes, so two people sharing a computer are not merged into one visit.

Each session records its entry page, exit page, number of pageviews and events, duration, source, channel and UTM tags. Sessions are a convention, so TapCub reports visitors and pageviews directly as well — you do not have to go through the session lens to answer "how many people" or "how many views".

Common mistakes

• Treating sessions as people. One person can create many sessions. Use visitors or identified users when the question is about people.
• Self-referrals. If your checkout runs on another domain and comes back, the return can start a new session with your own site as the source. Exclude your own domains from referrers.
• Changing the timeout mid-year. A longer timeout merges sessions and lowers the count. Note the date if you change it, or year-on-year comparisons break.
• Tagging internal links with UTM. In tools that restart sessions on campaign changes, UTM tags on links inside your own site split one visit into several and overwrite the real source.

Related guides: Average Session Duration and Engagement Metrics. See also engaged session and pages per session.