Business
Customer Churn Rate Calculator
Calculate the percentage of starting customers lost during a period.
- Free to use
- Runs in your browser
- Level B · Industry formula
- Last reviewed 2026-08-16
Calculator guide
How to use the Customer Churn Rate Calculator
Calculate the percentage of starting customers lost during a period. Enter the requested values and select Calculate. The result and supporting values are produced locally in your browser.
Formula
Worked example
Losing 80 of 2,000 starting customers is a 4% churn rate.
What to keep in mind
- Use a consistent period and customer population definition.
- Growth from new customers does not reduce churn under this starting-customer definition.
Methodology
This calculator uses deterministic arithmetic and performs the calculation locally in your browser. Verify assumptions, units, and source values for your specific use case.
Review standard: Level B · Industry formula. How calculator reviews work.
Frequently asked questions
What does this calculator calculate?
Calculate the percentage of starting customers lost during a period.
How is the result calculated?
Customer Churn Rate = Customers Lost ÷ Customers at Start × 100.
Can I use the result for an important decision?
Use the result as a calculation aid and verify the inputs, assumptions, and applicable professional or regulatory requirements before relying on it for an important decision.
Does CalculateMeasure store the values I enter?
The calculator performs its arithmetic in your browser. The calculator itself does not need to send your entered values to a server to produce the result.