About the Churn Rate Calculator
What is the Churn Rate Calculator?
Churn rate is the share of customers who leave in a period. Small monthly numbers compound: 2.5% a month means losing over a quarter of customers in a year.
Enter customers at the start of the period, customers lost and the length of the period. The calculator converts churn into monthly and annual rates for comparison.
How to use the Churn Rate Calculator
- Customers at the Start of the Period (sample: 2,000)
- Customers Lost During the Period (sample: 150)
- New Customers Added (sample: 260)
- Length of the Period (months) (sample: 3)
- Press Calculate Churn Rate (results also refresh as you type). The result card shows the Churn Rate for the Period, along with Monthly churn rate (compounded), Annual churn rate, Retention rate for the period and Customers at the end.
Formula used
Churn = Customers lost ÷ Customers at the start of the period
- Monthly churn = 1 − (1 − period churn)^(1 ÷ months)
- Annual churn = 1 − (1 − monthly churn)¹²
New customers added during the period are not in the denominator.
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Customers at the Start of the Period | 2,000 |
| Customers Lost During the Period | 150 |
| New Customers Added | 260 |
| Length of the Period (months) | 3 |
| Result | Value |
|---|---|
| Churn Rate for the Period | 7.5% |
| Monthly churn rate (compounded) | 2.57% |
| Annual churn rate | 26.79% |
| Retention rate for the period | 92.5% |
| Customers at the end | 2,110 |
| Average customer lifetime | 39 months |
Tips for using the Churn Rate Calculator
- Measure churn by signup cohort to see whether onboarding is improving.
- Ask departing customers why they leave; the reasons point to fixes.