Can you afford to pay more per customer?
Your breakeven CAC is the floor. Repeat purchases raise the ceiling. Enter your numbers to see customer lifetime value, your LTV:CAC ratio, and how long it takes to earn back what you spend acquiring a customer.
Founders & growth · ~2 min
Needs: Order value/ARPA, retention, CAC
Your numbers
Gross-margin economics for a repeat-purchase business.
Result
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The total gross profit one customer brings over their lifetime.
A 3:1 ratio is sometimes used as a general reference, but the right target depends on margin, cash position, retention, growth stage and business model. Allowable CAC at that 3:1 reference: —.
Months of gross profit to earn back CAC. Shorter means less cash tied up.
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Honest caveat:
this is a gross-margin LTV, and it's only as good as your retention inputs — lifespan, churn, or repeat rate — which most businesses estimate rather than measure. Treat the result as a modelled ceiling, not a fact, until you can pull real cohort retention. The 3:1 reference is a rule of thumb, not a law: a cash-tight startup may need faster payback, while a high-margin, low-churn business can justify going lower. Getting that retention measurement right is the foundation work we do first.
Guessing your repeat rate? That's the real problem
LTV is only as trustworthy as the retention data behind it. A Foundation Audit checks whether your analytics can actually measure repeat purchases and cohort retention — before you bet a higher CAC on a number you can't see.
Discuss your growth project