Churn
Monthly Churn Cost Calculator.
Churn cost is the dollar value of the customers you lost this month. Multiply your current customer count by your monthly churn rate to get customers lost, then multiply by ARPU to get the dollar leak. A 100-customer SaaS at $49 a month with 5 percent monthly churn loses $245 every month – $2,940 a year – before adding a single new customer. That is the floor your acquisition has to clear just to stay flat. Founders who run this calc once usually start their next sprint on retention, not ads.
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Formula
Monthly $ lost = Customers × Monthly Churn % × ARPUCalculator
Inputs
Result
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Frequently asked
- Why does monthly churn matter so much?
- Because it compounds. At 5 percent monthly churn, you lose roughly 46 percent of your customer base every year. The first cohort you acquire is more than half gone twelve months later.
- Is gross or net churn the right number to use here?
- Gross churn (customers who fully cancel) for this calculator. Net revenue churn adds back expansion revenue from upgrades, which masks the retention problem. If you want to see the leak, use the gross number.
- What counts as a low monthly churn rate for indie SaaS?
- Anything under 3 percent monthly is healthy for SMB-tier SaaS. 5 to 7 percent is normal for a young product. Above 10 percent is a leaking bucket – fix retention before scaling acquisition.
Related calculators
- SaaS LTV Calculator – How much gross profit does each customer produce before they churn? One formula. Three inputs.
- Post-Launch Revenue Projector – Where does your MRR actually land in twelve months given your real churn and acquisition rate? See the curve.
- CAC Payback Period Calculator – How many months of gross profit does it take a paid customer to pay back their acquisition cost? Below twelve, you can scale.
- Pricing Power Calculator – What happens to LTV, payback, and LTV-to-CAC if you raise your price 50 percent? Side-by-side answer.