Subscription Churn Impact Calculator

Model customer and recurring-revenue trajectory from constant churn, acquisition, ARPU, and horizon assumptions.

Each month applies churn to opening customers, then adds the entered acquisitions. This is a bounded constant-rate scenario, not a cohort forecast.

Results will appear here.

Planning estimate only. Platform fees, taxes, payment costs, and policies can change; verify current terms before pricing.

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How this calculator works

Reviewed July 2026

Formula

Each month, churned customers = opening customers × monthly churn; ending customers = opening customers − churned customers + new customers. Monthly revenue = ending customers × ARPU.

Worked example

1,000 customers, 5% monthly churn, no acquisition, and $20 ARPU leave about 540 customers and $10,807 monthly revenue after 12 modeled months.

Assumptions to verify

  • Churn, acquisition, and ARPU remain constant throughout the horizon.
  • Churn is applied before new customers are added each month.
  • Cohorts, expansion revenue, reactivation, seasonality, failed payments, and acquisition lag are excluded.

Frequently asked questions

When is churn applied?

To opening customers before the entered new customers are added.

What is replacement need?

Month-one customers expected to churn at the entered rate; rounding up gives a whole-customer planning target.

Is this a retention forecast?

No. It is a bounded constant-rate scenario without cohort behavior.

Privacy: Inputs and results stay in this browser. Any future sponsored recommendation or advertisement will be clearly labeled and kept separate from the calculation.