What is break-even ACoS?

Break-even ACoS is the percentage of revenue you can spend on Amazon advertising before the product stops being profitable. If your margin is 27%, you can spend up to 27% of revenue on ads before losing money.

Does the calculator include overhead?

It supports an optional per-unit overhead input to approximate returns, storage, or amortized costs. Leave it at 0 for a pure contribution margin view.

What referral fee should I use?

Most Amazon categories use 15%. Some accessories, jewelry, and media categories use different tiers — check Amazon Seller Central for your specific category.

Amazon FBA Calculator

Net profit, margin, and break-even ACoS. All numbers update as you type.

How to read the results

Net profit is revenue minus Amazon referral fee, FBA fulfillment fee, COGS + inbound shipping, and any overhead you entered.
Margin is net ÷ revenue, as a percentage.
Break-even ACoS equals the margin — spend less than this % on PPC and you keep some profit; spend more and ads eat the product.