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Investor Churn Calculator

The Investor Churn Calculator calculates gross customer churn and gross revenue churn for a selected period. Customer churn compares lost customers with customers at the start of the period, while revenue churn compares recurring revenue lost from churned or contracted accounts with starting recurring revenue.

Presenting both metrics helps investors distinguish account loss from economic loss. A company can have modest customer churn but high revenue churn when larger accounts leave, or the reverse when many small accounts churn. The calculator intentionally excludes expansion revenue from gross revenue churn. For a net revenue retention view, expansion, contraction, and reactivation should be modeled separately.

Inputs

customers
customers
USD
USD
Result
—
Gross recurring revenue churn
Gross customer churn—
Customers lost—
Recurring revenue lost—

1. Set the measurement period
Use one consistent month, quarter, or year for every input.

2. Enter starting customers
Count customers active at the beginning of the period.

3. Enter customers lost
Count beginning-period customers that fully churned.

4. Enter starting and churned MRR
Use recurring revenue at the start and recurring revenue lost from churned accounts.

5. Compare customer and revenue churn
The difference indicates whether churn is concentrated in larger or smaller accounts.

Customer churn = Lost customers ÷ Starting customers × 100; Revenue churn = Churned MRR ÷ Starting MRR × 100

Where:

  • Lost customers = beginning-period customers that fully left
  • Starting customers = active customers at period start
  • Churned MRR = recurring revenue lost from churn
  • Starting MRR = recurring revenue at period start

Assumptions: The model uses gross churn and excludes new sales, expansion, and reactivation. All inputs cover the same period.

What the result means

Gross recurring revenue churn.

Use the result as a planning estimate based on the assumptions above.

Given: A company starts the month with 420 customers and $168,000 MRR. It loses 18 customers representing $10,500 MRR.

Calculation: Customer churn: 18 ÷ 420 × 100 = 4.2857%. Revenue churn: $10,500 ÷ $168,000 × 100 = 6.25%.

Result: Revenue churn is higher than customer churn, indicating the lost customers were above average in recurring revenue.

Should new customers be included in the denominator?

No. Gross churn uses the customer and revenue base present at the start of the period.

What is the difference between gross and net revenue churn?

Gross revenue churn ignores expansion and reactivation. Net churn offsets losses with those gains.

Can partial downgrades be included?

This calculator labels the input churned MRR. Include contraction only if your reporting policy defines it as churn; otherwise track it separately.

Why might customer churn be higher than revenue churn?

The business may be losing many low-value accounts while retaining larger customers.

How should annual-plan customers be measured monthly?

Use a consistent monthly recurring revenue allocation and a clear churn date policy.