Business calculator
Free Customer Churn Rate Calculator
Calculate customers lost, remaining customers, and churn rate over a period.
Customer Churn Rate Calculator
Use consistent start and end periods when comparing churn rates.
Understand the result
Measure customers lost during a period
Customer churn rate divides customers lost during a period by customers at the start of that period. It is most useful when the start count and loss count use the same definition and timeframe.
Focused formula
The result uses only the inputs relevant to this business question.
Private in your browser
Values are calculated locally and are not stored or sent anywhere.
Use the calculator
Enter the figures you already have
- 1
Add your inputs
Use the labels and period shown in the form.
- 2
Review the math
Results update as your assumptions change.
- 3
Apply the result
Use it as a planning reference for the next decision.
What churn means
Churn is the share of the starting customer base lost during the selected period. Remaining customers equal starting customers minus customers lost.
Period consistency
Compare like-for-like periods and definitions. Contract cancellations, inactive users, and revenue churn are not interchangeable measures.
Worked example
With 1,000 starting customers and 100 lost customers, 900 remain and the churn rate is 10%.
Frequently asked questions
Practical questions people ask about this tool
What if lost customers exceed the starting count?
The calculator shows a validation message because the simple customer-count model cannot produce more losses than the starting base.
How is churn related to retention?
Both describe customer movement, but churn focuses on losses while retention focuses on starting customers kept.
What if starting customers is zero?
Churn is not calculable because the starting denominator is zero.
Can I use this for revenue churn?
No. This calculator measures customer-count churn; revenue churn needs revenue inputs and a different formula.
Related tools
Related business tools
Customer Retention Rate Calculator
Calculate customers retained.
Customer Lifetime Value Calculator
Estimate customer lifetime value.
Monthly Recurring Revenue Calculator
Estimate recurring revenue.
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