How to use the Churn Rate Calculator

Calculate customer churn and retention percentages from period-start customers and losses.

Calculation formula

Customer churn (%) = customers lost during period ÷ customers at start × 100; retention (%) = 100 − churn.

Recommended steps

1. Enter values using the units shown beside each field.
2. Review whether the example assumptions match your situation.
3. Run the calculator and compare the key metrics.
4. Use the source data or official rates when precision matters.

Known limitations

Do not include newly acquired customers in starting base; specify the same period when comparing churn rates.