Session Duration
AnalyticsAlso: Average session duration · Time on site · Visit duration
Quick definition
Session duration measures how long a visitor spends on your website during a single visit. In GA4, this is reported as average engagement time, which measures time the browser is active in the foreground rather than total session time.
Where it shows up in the data
Universal Analytics tracked total session time from first to last hit. GA4 tracks 'average engagement time', which only counts time when the browser tab is active and in the foreground. GA4 figures are typically lower than UA figures for the same site.
GA4's replacement metric for bounce rate. A session is 'engaged' if it lasts longer than 10 seconds, has a conversion event or views more than one page. Engagement rate is the proportion of sessions that qualify as engaged.
Long session duration is not inherently good. A user spending 15 minutes on a checkout page may be confused. A user converting in 60 seconds is ideal. Always interpret session duration in the context of the page's purpose.
The number of pages viewed per session, also called pages per session. Combined with session duration, it indicates whether users are exploring your site or landing, reading one thing and leaving.
What it actually means
Session duration is a proxy for engagement. Users who read your content, browse your product range or compare your service options tend to spend more time. Users who land, do not find what they need and bounce spend less. But session duration without conversion data is only half the story. Some of the best performing pages on high-converting sites have very short sessions because the message is clear and the action is immediate.
Long sessions are not success. Fast conversions are success. Measure time on site in the context of what you actually want visitors to do.
How to calculate it
Session duration = Time of last event - Time of first event in that session In GA4: Average engagement time per session = Total engaged time / Total sessions
Worked example. 100 sessions. Total engaged time across all sessions: 350 minutes. Average engagement time = 3.5 minutes per session. Separately, sessions under 30 seconds have 1% conversion rate. Sessions 1-3 minutes have 4% conversion rate. Sessions over 3 minutes have 8% conversion rate.
The Australian context
Australian news and media sites typically see higher average session durations than retail sites. The ACCC and regulatory body sites see unusually long sessions due to complex document reading. For B2B professional services in Australia, average engagement times of 2 to 4 minutes on service pages are typical before a contact form submission.
Where people get this wrong
Related terms
Common questions
What is a good average session duration?
It depends entirely on your content and goals. For blog posts: 2 to 4 minutes is healthy. For product pages: 1 to 3 minutes. For landing pages designed for fast conversion: under 60 seconds can be excellent. Always compare against your own historical baseline and your conversion rate by session length.
Why did my session duration drop after switching to GA4?
GA4 measures active engagement time (tab visible and foregrounded), while Universal Analytics measured total elapsed session time. GA4 figures are typically 20-40% lower than UA for the same behaviour. This is a measurement change, not a real decline in engagement.
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New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.
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