CAC Payback Period Calculator

The CAC payback period is the number of months of gross profit from a customer that it takes to recover the cost of acquiring them. It is calculated as customer acquisition cost divided by the monthly gross profit per customer (monthly revenue times your gross margin). The shorter the payback, the faster your spend turns back into cash you can reinvest.

It varies by business and funding model, but under 12 months is generally considered healthy for SaaS and subscription companies, and many efficient businesses aim for 6 months or less. A payback well over 18 to 24 months can strain cash flow because you wait a long time before an account becomes profitable.

Because you only recover CAC from the profit a customer generates, not their full revenue. If you charge 50 dollars a month but it costs you 10 dollars to serve them, only 40 dollars goes toward paying back acquisition. Using gross margin instead of raw revenue gives a true contribution-margin payback. Leave margin at 100 percent for a simpler revenue-based payback.

Payback period measures speed, how fast you get your money back, while LTV:CAC measures total return over a customer's lifetime. Two businesses can share the same LTV:CAC ratio yet have very different paybacks. Healthy companies usually track both: a strong ratio and a short payback together.

No. The calculation runs entirely in your browser, so the CAC, revenue and margin figures you type never leave your device. Nothing is uploaded or stored.