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Founder Viability — the maths
Four numbers. One verdict.
Gross margin, LTV, LTV:CAC, payback period. These four ratios tell you whether your business model works. Enter your numbers and get the maths and the lever to pull. Indicative only — not financial advice.
1.Average revenue per customer per month (USD)
For one-time purchases, divide annual revenue by customer count.
2.Average cost to serve one customer per month (USD)
Direct costs only: hosting, support, payment processing, COGS. Not salaries.
3.Customer acquisition cost (CAC) — total (USD)
Total sales + marketing spend in a period ÷ new customers acquired in that period.
4.Monthly churn rate (%)
Percentage of customers who cancel each month. For annual contracts, divide annual churn by 12.
Answer all questions to continue.