Glossary

Sessions (GA4)

A session is one visit to your website: it starts when a user arrives and ends after 30 minutes of inactivity. One user can have many sessions. Sessions measure visit volume, the standard unit for 'how much traffic did the campaign send?'.

How to read it

Compare sessions from paid channels against ad clicks: they won't match exactly (different counting), but their trend lines should move together.

Where it misleads

A user returning after 31 minutes is a new session; session counts rise with fragmented browsing behavior, not only with more visitors.

Related terms

Active Users (GA4) →

Active users is GA4's primary user metric: the number of distinct people who had an engaged session or fired a first-visit/engagement event in the period. It replaced Universal Analytics' 'users' as the default headcount of your website audience.

Engagement Rate (GA4) →

Engagement rate is the share of sessions that were 'engaged': lasted over 10 seconds, had a key event, or included at least two page views. It's GA4's inverse of the old bounce rate: it measures how many visits showed any real interaction.

Avg. Session Duration (GA4) →

Average session duration is the mean time visitors spent on your site per session. It approximates depth of interest: longer sessions usually mean content that holds attention. For ad traffic, it shows whether clicks brought people who actually wanted to be there.

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