Calculator inputs
Use the fields below to model subscription acquisition, churn, retention, reactivation, and revenue.
Example data table
The table below shows a sample six-month subscription scenario using 1,000 starting subscribers, 150 monthly new subscribers, 4% churn, 3% acquisition growth, 10% reactivation, and $20 ARPU.
| Month | Opening | New | Churned | Reactivated | Closing | MRR ($) |
|---|---|---|---|---|---|---|
| 1 | 1,000.00 | 150.00 | 40.00 | 4.00 | 1,114.00 | 22,280.00 |
| 2 | 1,114.00 | 154.50 | 44.56 | 4.46 | 1,228.40 | 24,567.92 |
| 3 | 1,228.40 | 159.14 | 49.14 | 4.91 | 1,343.31 | 26,866.17 |
| 4 | 1,343.31 | 163.91 | 53.73 | 5.37 | 1,458.86 | 29,177.17 |
| 5 | 1,458.86 | 168.83 | 58.35 | 5.84 | 1,575.17 | 31,503.32 |
| 6 | 1,575.17 | 173.89 | 63.01 | 6.30 | 1,692.35 | 33,847.02 |
Formula used
1) Projected new subscribersNew_t = BaseNew × (1 + AcquisitionGrowthRate)^ (t - 1)
2) Churned subscribersChurned_t = OpeningSubscribers_t × ChurnRate
3) Reactivated subscribersReactivated_t = Churned_t × ReactivationRate
4) Net addsNetAdds_t = New_t + Reactivated_t - Churned_t
5) Closing subscribersClosing_t = Opening_t + NetAdds_t
6) Net growth rateNetGrowthRate_t = (NetAdds_t ÷ Opening_t) × 100
7) Retention rateRetentionRate_t = ((Opening_t - Churned_t + Reactivated_t) ÷ Opening_t) × 100
8) Monthly recurring revenueMRR_t = Closing_t × ARPU
9) Compound monthly growth rateCMGR = ((Ending ÷ Starting)^(1 ÷ Months) - 1) × 100
How to use this calculator
Enter your current subscriber count, the expected number of new subscribers added each month, and the share that churns monthly. Then add acquisition growth and reactivation assumptions to capture realistic movement.
Set the average revenue per user to estimate recurring revenue. Choose the number of months for your projection horizon and optionally enter a target subscriber goal.
Press Calculate Growth Projection. The result section appears below the header and above the form area, showing summary metrics, a Plotly graph, and a detailed month-by-month projection table.
Use the export buttons to save the generated table as CSV or PDF for reporting, dashboard reviews, internal planning, investor decks, or growth experiments.
Frequently asked questions
1) What does this calculator measure?
It estimates subscriber growth across future months by combining new acquisitions, churn, reactivation, retention, and recurring revenue. It helps turn simple assumptions into a structured projection.
2) What is churn rate?
Churn rate is the percentage of active subscribers who cancel during a month. Higher churn reduces net adds, lowers ending subscribers, and can weaken recurring revenue quickly.
3) Why include reactivation rate?
Reactivation rate estimates how many churned subscribers return. Including it makes the forecast more realistic for businesses running win-back campaigns or renewal nudges.
4) What is acquisition growth rate?
It represents the month-over-month change in new subscriber signups. Positive values grow acquisitions over time, while negative values model slowing demand.
5) What does CMGR mean here?
CMGR means compound monthly growth rate. It smooths the whole projection into one monthly rate, making performance easier to compare across scenarios.
6) Can this calculator estimate revenue too?
Yes. By multiplying projected ending subscribers by average revenue per user, it estimates monthly recurring revenue and its growth across the selected period.
7) Is this useful for Data Science work?
Yes. It provides a clean scenario model for growth experiments, sensitivity analysis, forecast reviews, dashboard validation, and business planning discussions.
8) Are the results exact predictions?
No. The calculator produces scenario-based estimates from your assumptions. Results improve when your churn, acquisition, pricing, and reactivation inputs reflect real historical data.