Churn is the opposite of retention. Subscription businesses track it monthly; a 5% monthly churn means losing almost half of customers in a year. Reducing churn is usually cheaper than acquiring new customers.
How to use the Churn Rate Calculator
- Customers at the start of the period
- Customers lost during the period
- Period length
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the number of customers at the start of the period and how many cancelled during it.
Inputs explained
| Field | What to enter |
|---|---|
| Customers at the start of the period | A number |
| Customers lost during the period | A number |
| Period length | Choose one: Month, Quarter, Year |
What each result means
- Churn rate = [Customers lost during the period]÷[Customers at the start of the period]×100
- Retention rate = 100 – [Churn rate]
- Average customer lifetime = [Customers at the start of the period]÷max([Customers lost during the period], 0.000001)
- Annualised churn = (1 – (1 – [Churn rate]÷100)^[Period length])×100
Example values
How the main result changes when Customers at the start of the period changes and everything else stays at the example values above:
| Customers at the start of the period | Churn rate (%) |
|---|---|
| 1,000 | 7 |
| 1,500 | 4.67 |
| 2,000 | 3.5 |
| 2,500 | 2.8 |
| 3,000 | 2.33 |
| 4,000 | 1.75 |
Formula
Churn rate = customers lost ÷ customers at the start × 100
Average customer lifetime = 1 ÷ churn rate (in periods)
Annual churn = 1 − (1 − monthly churn)¹²
Worked example
Inputs: Customers at the start of the period: 2,000; Customers lost during the period: 70; Period length: Month.
Results: Churn rate = 3.5 %; Retention rate = 96.5 %; Average customer lifetime = 28.6 periods; Annualised churn = 34.79 %.
Frequently asked questions
What is a good churn rate?
For B2B SaaS, under 1–2% a month; consumer subscriptions are often 5–7%.
How is customer lifetime related to churn?
Lifetime is roughly 1 ÷ churn: 5% monthly churn means about 20 months.
Should new customers count?
No. Measure churn on customers present at the start of the period.