Retention Rate: measuring the customers who stay

Retention Rate is the share of customers or users who remain with a product over a chosen period. “Remain” may mean an active subscription, a repeat purchase or meaningful product use. Pick a definition before comparing numbers.

Divide the number of customers from the starting group who remain at the end by the number in that group at the start, then multiply by 100%. If 80 of 100 starting customers remain after a month, that group's retention is 80%. Customers acquired during the month are not added to this starting group.

Choose a measurement window that matches the product's normal usage cycle. A daily tool and an occasional high-value purchase need different windows.

Group customers by first-use date, plan or acquisition channel. This reveals whether newer groups are doing better after a product change. A single average may hide a problem while acquisition is growing.

Look for the point where customers stop returning: first use, reaching value, renewal or support. Compare behavioural data with interviews and tickets. The rate shows where to investigate; it does not explain the cause on its own.