Cohort Retention Calculator
The height of the flat tail is what matters.
12-month retention
12%
80% of month-6 customers survived to month 12
The curve is flattening — customers who reach month six mostly stay. That flat tail is the durable part of the business, and its height is what determines lifetime value more than the early drop does.
How the Cohort Retention Calculator works
A retention curve that flattens means you have found a group for whom the product works. The height at which it flattens determines lifetime value far more than the steepness of the early drop — and a curve that never flattens points at the product rather than at onboarding.
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
What is cohort retention?
The share of a group acquired in one period who are still active in each subsequent period. It separates genuine retention from the noise a blended figure produces.
What does a flattening curve mean?
That churn has stopped being a function of newness. The customers who remain have found their reason to stay, and they are the durable part of the business.
Why measure by cohort at all?
Because a blended retention rate mixes mature customers with recent ones and moves whenever acquisition volume changes. It can improve while retention genuinely worsens.
How long should I track cohorts?
Until the curve is visibly flat, which for most consumer businesses is six to twelve months. Extrapolating lifetime value from three months of data consistently overstates it.