The Retention topic helps you understand how frequently and for how long users engage with your website or mobile app after their first visit. The topic also helps you understand how valuable users are based on the additional revenue you generate after their first visit.
New and returning users
New users are users who visit your site or app for the first time. Analytics identifies a new user as anyone who doesn't have both a Google Analytics cookie and Client ID from your site or App Instance ID from your app. Users who already have these are returning users.
A cohort is a group of users who share a common characteristic identified by an Analytics dimension. For example, all users with the same Acquisition Date belong to the same cohort. In the Retention topic, new users are part of the same cohort.
User retention by cohort
The User retention by cohort chart shows the percentage of new users who return on their second and eighth day. For example, 100 users visit your site on September 9. Ten of the users return on September 10 and two return on September 16. The Day 1 line shows 10% on September 10, while Day 7 shows 2% on September 16.
User engagement by cohort
The User engagement by cohort chart shows the average engagement time of new users who return to your site or app on their second and eighth day. Analytics includes only returning users in the average engagement time.
This chart shows the percentage of users who return each day in their first 42 days. The chart starts with 100% user retention when all users visit for the first time. It decreases from the first day as users drop off.
The User engagement chart shows the average engagement time of users who return in their first 42 days. Analytics includes only returning users in the average engagement time.
The Lifetime value chart illustrates the average revenue from new users over their first 120 days. You can use the chart to determine how valuable users are based on additional revenue you generate. For example, a user purchases a shirt and then purchases pants the following week. Lifetime value (LTV) includes both purchases, indicating the overall success of the acquisition.