Average Customer Lifespan Calculator
The average hides the shape.
Average lifespan
25.0 months
half the cohort gone in 17.0 months
Average lifespan is one divided by churn, but the average hides the shape — half the cohort is gone in 17.0 months while a tail survives far longer. Planning against the average overestimates how long the typical customer stays.
How the Average Customer Lifespan Calculator works
Average lifespan is one divided by churn, but the average conceals the shape — half a cohort is typically gone in well under the average, while a tail survives far longer. Planning against the mean overestimates how long the typical customer stays.
Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price — check the platform's current fee schedule before you price a product against it. This is not tax or business advice.
Frequently asked questions
How do I calculate average customer lifespan?
One divided by the churn rate. At 4% monthly churn, the average lifespan is 25 months.
What is the half-life?
The point at which half the cohort has churned, which is always shorter than the average. At 4% monthly churn the half-life is about 17 months against a 25-month average.
Why does the distinction matter?
Because cash arrives on the half-life schedule, not the average one. Modelling revenue on the average overstates the near term and understates the tail.
Does churn stay constant?
Usually not — it is highest early and falls for survivors. That makes a single churn figure an approximation, and it means cohort curves are worth building for anything important.