Free tool
Max Customer Acquisition Cost Calculator
"How much should I spend on marketing?" is really "how much can I pay for one customer and still profit?" This calculator answers it two ways — the cautious ceiling (profit on the first purchase alone) and the growth ceiling (profit across the customer lifetime) — with your target margin built in.
Choosing your ceiling
First-purchase payback is the conservative rule: acquisition cost recovered before the customer even returns, so cash flow stays safe. It suits tight cash and unproven repeat rates. The lifetime ceiling spends future profit to buy growth — right when your repeat business is real and measured, and how funded competitors will out-bid you if you stay on the cautious rule while they play the longer game.
Wherever you set it, the ceiling is a budget discipline: any channel whose cost per customer exceeds it is shrinking your business per sale, whatever its dashboard says.
Common questions
What target profit percentage should I use?
It is your choice of safety margin: 0% finds true break-even; 30–50% keeps meaningful profit per acquired customer. Start at 30% and loosen it only for channels whose numbers you trust.
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