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.
Tips
- Use figures for the same period (a month, a quarter or a year) for every input so ratios compare like with like.
- Track the metric over time – the trend usually tells you more than a single value.
- Compare your result with industry benchmarks, which vary a lot between sectors.
- Treat the result as a starting point for a decision, then check the assumptions behind each input.
Common mistakes to avoid
- Mixing monthly and yearly numbers in the same calculation.
- Using revenue where the formula needs profit (or the other way round).
- Forgetting hidden costs such as taxes, fees, overheads or your own time.
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 × 100Average customer lifetime = 1 ÷ churn rate (in periods)Annual churn = 1 − (1 − monthly churn)^12Worked 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.
What formula does the Churn Rate Calculator use?
Churn rate = customers lost ÷ customers at the start × 100.