Free tool
Churn and retention calculator
Customer churn, retention, annualised churn plus net and gross revenue retention.
Customers
Revenue (optional)
Churn rate
5.0%
Retention rate
95.0%
Customers at end
220
Annualised churn
If this monthly rate continues
46.0%
Expected lifetime
20.0 months
Net revenue retention
100.0%
Gross revenue retention
90.0%
What it calculates
Churn is the share of customers you lose in a period. Retention is its mirror image. Revenue retention goes a step further and asks how much of last period's recurring revenue is still there, counting upgrades and downgrades.
The formula
- Churn rate = customers lost / customers at start
- Retention rate = 1 - churn rate (new customers are excluded)
- Annualised churn = 1 - (1 - monthly churn)^12
- Expected lifetime in months = 1 / monthly churn
- NRR = (start MRR + expansion - contraction - churned) / start MRR
- GRR = (start MRR - contraction - churned) / start MRR
Worked example
200 customers, 10 lost, 30 new
- Churn = 10 / 200 = 5.0 percent, retention = 95.0 percent
- Customers at end = 200 - 10 + 30 = 220
- Annualised churn = 1 - 0.95^12 = about 46.0 percent
- Expected lifetime = 1 / 0.05 = 20 months
- With start MRR Rs 1,00,000, expansion 10,000, contraction 5,000 and churned 5,000: NRR is 100 percent and GRR is 90 percent
Questions
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