FREE CALCULATOR · USD WHERE APPLICABLE
Customer churn calculator
Measure one opening customer group over one period. Keep new customers separate.
Your assumptions
The starting values are an editable example. These inputs are calculated in your browser and are not submitted to the server.
YOUR PLANNING ESTIMATE
- Customer churn
- 5%
- Customer retention
- 95%
- Opening customers remaining
- 190
Use one consistent period and active-customer definition. This is customer churn, not revenue churn. It does not predict future behavior.
Formula and scope
Customer churn = customers lost from the opening group ÷ opening customers × 100. Retention = (opening customers − customers lost) ÷ opening customers × 100.
Version 1.0.0 · September 14, 2026. Calculation source is available under the MIT license.
Inspect or reuse the codeWorked example
Worked example: losing 10 customers from an opening group of 200 gives 5% churn and 95% retention. It does not measure revenue churn or include new customers.
Use the related practical guide →Check the meaning before comparing
These are simplified models. Your inputs determine the result. A calculated return is not a measured business outcome.
Read the metric definitions →Useful enough to pass along?
BIZORYN. “Customer churn calculator.” Updated September 14, 2026.
https://bizoryn.com/library/tools/customer-churnCredit is welcome. Linking is optional.
Source: https://bizoryn.com/library/tools/customer-churn · BIZORYN · Updated September 14, 2026