Total marketing & sales spend ÷ new customers
Average monthly revenue per customer
Leave blank to assume 100%
Enter CAC and ARPU on the left to see your payback period.
Payback Period — also called Months to Recover CAC — is the number of months it takes for the gross profit from a customer to repay what you spent acquiring them.
Payback = CAC ÷ (ARPU × Gross Margin %)
It directly drives cash flow. Long payback periods tie up capital and force outside funding to scale; short payback compounds growth from internal cash. Skok's targets: 5–7 months healthy, 12 months max before profitability suffers.
Most B2B SaaS companies improve payback by raising prices, front-loading annual contracts, or shifting acquisition spend to channels with shorter payback. The fastest lever is usually annual prepay — it turns a 12-month payback into a 1-month payback for that specific customer.
Saasly's free full SaaS metrics calculator computes payback alongside LTV, CAC, LTV:CAC, NRR, Quick Ratio, churn, and 15+ more — with trend analysis across three months and benchmark comparisons.
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