Churn rate
Churn rate is the share of customers who stop buying over a given period.
Churn is the loss of customers over time. For non-subscription e-commerce there's no explicit cancellation, so churn is usually defined behaviourally — a customer is considered churned if they haven't ordered within a window longer than their normal purchase cycle. Watching churn (and the segments most prone to it) tells you where win-back and loyalty efforts will pay off most.
How it's measured
Behavioural churn: customers with no order in N days ÷ active customers. Choose N based on your typical repurchase interval.
Related terms
Repeat purchase rate
Repeat purchase rate is the share of customers who have placed more than one order.
RFM analysis
RFM (Recency, Frequency, Monetary) scores customers on how recently and often they buy and how much they spend, to segment them for marketing.
Cohort analysis
Cohort analysis groups customers by a shared start point (e.g. first-order month) and tracks their behaviour over time.
Customer lifetime value (CLV / LTV)
Customer lifetime value is the total revenue (or profit) a customer generates across their entire relationship with your store.