What this calculator tells you
Break-even CPA is the ceiling for acquisition cost on one order. A target-profit CPA is lower than pure break-even because it reserves part of the contribution before advertising.
When to use it
Use it to set bid ceilings, compare channels, or decide whether a campaign is buying profitable customers rather than merely buying revenue.
Start with your landed cost, real fee rates, and a pessimistic advertising cost. The result is more useful when the assumptions are honest.
Using gross revenue as the CPA ceiling ignores product, fulfillment, and payment costs. The limit has to come from contribution, not the selling price.
Frequently asked questions
Is this the same as break-even ROAS?
They describe the same order economics from different angles. ROAS compares revenue with ad spend, while CPA states the maximum spend allowed per order.
What target profit should I use?
Choose a dollar reserve that supports overhead and risk. A zero target profit gives the pure break-even CPA, which leaves no contribution beyond variable costs.
Should refunds be included?
For a conservative ceiling, lower the selling price or increase the effective cost to reflect refunds and payment disputes.
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