Break-Even ACoS Calculator

Work out the ACoS where ad-driven orders stop making money, and the target ACoS that keeps a chosen profit margin.

Your numbers

▾

Per unit

Selling price

Referral fee rate

15% in most categories. Check the referral fee calculator for tiered categories.

FBA fulfillment fee

From the FBA calculator or your Fee Preview report. Enter 0 if you ship it yourself.

Product cost and freight in

Other costs per unit

Storage, packaging, returns you absorb.

Goal

Profit margin you want to keep after ads

Your result · updates as you type

Break-even ACoS

32.5%

Each unit leaves $8.13 before ads. Spend up to 32.5% of ad sales and ad orders still break even.

Target ACoS for 10% profit: 22.5%
Profit per unit before ads: $8.13
Max ad cost per order at break-even: $8.13

Set campaign targets at 22.5% ACoS to keep 10% of each ad sale as profit. Use the PPC bid calculator to turn that into a maximum bid.

Profit per ad-driven unit at each ACoS

10% ACoS

$5.63

15% ACoS

$4.38

20% ACoS

$3.13

25% ACoS

$1.88

30% ACoS

$0.63

35% ACoS

-$0.62

40% ACoS

-$1.86

Breakdown

Selling price: $24.99
Referral fee (15%): −$3.75
FBA fee: −$5.61
Product cost and freight: −$7.30
Other costs: −$0.20
Profit before ads: $8.13
Break-even ACoS = profit ÷ price: 32.5%
Target ACoS = break-even − 10% goal: 22.5%

How break-even ACoS is worked out

Break-even ACoS = (price − referral fee − FBA fee − product cost − other costs) ÷ price

Worked example (the calculator's starting values)

Price: $24.99
Referral fee (15%): −$3.75
FBA fee: −$5.61
Product cost and freight, other costs: −$7.30, −$0.20
Profit before ads: $8.13

Break-even ACoS is 8.13 ÷ 24.99 = 32.5%. For a 10% profit goal after ads, the target ACoS is 32.5% − 10% = 22.5%.

On a $14.99 item with a $3.34 FBA fee, $3.20 cost and $0.10 other costs, break-even ACoS is a much higher 40.7%, because fixed per-unit fees (the FBA fee, the $0.30 referral minimum) take a bigger share of a lower price.

Turning this into campaign targets

Set campaign ACoS targets below break-even, at the level shown for your chosen profit goal, so ad-driven orders keep the margin you actually want, not just avoid a loss.
Get FBA fee and referral rate from the real tools. Use the FBA calculator and referral fee calculator instead of guessing.
Turn a target ACoS into a bid with the PPC bid calculator, using your conversion rate.

Questions people ask

What is break-even ACoS?

The ACoS at which an ad-driven order earns exactly zero profit: ad spend for that order equals what's left after product cost and Amazon fees. It equals your profit margin before ad costs.

How do I calculate my break-even ACoS?

Subtract the referral fee, FBA fee, product cost and any other per-unit costs from the price, then divide by the price. This calculator does it for you.

Should I aim for break-even ACoS or below it?

Below it, if you want ads to add profit rather than just cover their own cost. Set a target ACoS below break-even by the profit margin you want to keep on ad-driven sales.

Why is my break-even ACoS so low on a cheap product?

Fixed per-unit costs like the FBA fee and the referral fee minimum take a bigger share of a low price, leaving less room for ad spend before an order stops being profitable.

Does this include storage fees?

No, only the referral fee, FBA fulfillment fee and the per-unit costs you enter. Add a monthly storage estimate per unit into Other costs per unit if it matters for your product.

Last reviewed 30 September 2026.

Sources: Amazon Ads: What is ACOS? · Amazon: Selling fees (referral fees by category) · Amazon: 2026 US FBA fulfillment fee changes