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SaaS Churn Calculator

The SaaS Churn Calculator measures customer churn, revenue churn, and net revenue churn for a selected period. It separates lost customers and lost recurring revenue from expansion revenue, giving a clearer picture of how much of the existing subscription base is being retained.

Use it for monthly or quarterly cohort reviews, operating dashboards, and renewal analysis. Customer churn answers how many accounts were lost, while gross revenue churn shows the recurring revenue lost before expansion. Net revenue churn offsets losses with upgrades or expansion from retained customers. Keeping the period consistent across all inputs is essential; mixing monthly starting customers with quarterly losses produces a misleading rate.

Churn period inputs

customers
customers
USD
USD
USD
Result
—
Customer churn rate
Customer churn—
Gross revenue churn—
Net revenue churn—
Ending customers before new sales—

1. Choose one reporting period
Use the same month, quarter, or year for every field.

2. Enter the opening customer count
Count active customers at the beginning of the period, before new sales.

3. Enter customer losses
Include cancellations or nonrenewals from the opening customer base.

4. Enter opening and churned MRR
Use recurring revenue at the start and the amount lost from that same base.

5. Add expansion MRR
Enter upgrades or added recurring revenue from retained customers; do not include revenue from brand-new customers.

6. Compare customer and revenue churn
Use the gap between rates to understand whether larger or smaller accounts are churning.

Customer churn rate = Lost customers ÷ Starting customers × 100
Gross revenue churn = Churned MRR ÷ Starting MRR × 100
Net revenue churn = (Churned MRR − Expansion MRR) ÷ Starting MRR × 100

New customer revenue is excluded because churn focuses on movement within the opening customer base. Net revenue churn can be negative when expansion from retained customers exceeds churned recurring revenue.

What the result means

The main result shows the percentage of opening customers lost during the selected period.

Always compare churn rates calculated over the same interval and with the same customer definition.

Given: 1,000 starting customers, 35 lost customers, $200,000 starting MRR, $12,000 churned MRR, and $5,000 expansion MRR.

Calculation: Customer churn = 35 ÷ 1,000 × 100 = 3.5%. Gross revenue churn = $12,000 ÷ $200,000 × 100 = 6.0%. Net revenue churn = ($12,000 − $5,000) ÷ $200,000 × 100 = 3.5%.

Result: Customer churn is 3.5%, while gross revenue churn is higher, indicating lost accounts were above average in revenue value.

Can net revenue churn be negative?

Yes. Negative net revenue churn means expansion from retained customers exceeded revenue lost to churn during the period. This is also described as net revenue retention above 100%.

Should new customer revenue be entered as expansion?

No. Expansion should come from customers already present at the beginning of the period. Revenue from newly acquired customers belongs in growth reporting, not churn.

What if one customer has several subscriptions?

Use a consistent customer definition. If you count accounts rather than subscriptions at the start, count lost accounts rather than canceled subscription lines.

Why is revenue churn higher than customer churn?

That usually means the customers lost carried more recurring revenue than the average opening customer. The reverse suggests churn was concentrated among smaller accounts.

How do refunds affect churn?

A refund is not automatically recurring revenue churn. Include it only if it represents a permanent reduction or cancellation of recurring revenue.