Amazon PPC break-even ACOS & target ACOS calculator (US)
The one number that decides whether an Amazon ad makes or loses money is your break-even ACOS. Enter your price and profit before ads to get it — plus your break-even ROAS, whether your current ACOS is profitable, and the target ACOS for a profit goal. Nothing is hard-coded, and nothing leaves your browser.
Profitable: your 25.0% ACOS is under the 35.0% break-even, keeping $3.00 per ad sale.
Your numbers
- Break-even ACOS
- 35.0%
- Break-even ROAS
- 2.86×
- Current ACOS
- 25.0%
- Current ROAS
- 4.00×
- Profit / ad sale
- $3.00
- Target ACOS
- 21.7%
Profitable: your 25.0% ACOS is under the 35.0% break-even, keeping $3.00 per ad sale.
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How it's worked out
- Break-even ACOS = profit before ads ÷ selling price. Break-even ROAS = 1 ÷ break-even ACOS.
- Current ACOS = ad spend ÷ ad sales. Current ROAS = ad sales ÷ ad spend.
- Profit per ad sale = profit before ads − (current ACOS × selling price). Positive means you make money on advertised sales; negative means you lose it.
- Target ACOS = (profit before ads − your target profit) ÷ selling price — the ACOS that leaves your chosen profit per unit after ads.
These are estimates from the figures you enter. ACOS also affects organic rank, and TACOS (total ad spend ÷ total sales) is worth watching alongside it — but break-even ACOS is the line that keeps each ad sale profitable.
PPC questions Amazon US sellers ask
What is break-even ACOS?
The advertising cost of sale at which an ad-driven order makes no profit and no loss. It equals your profit before advertising divided by the selling price. If a $30 unit makes $9 of profit before ads, break-even ACOS is 30% — spend up to 30% of that sale on ads and you break even. Keep your ACOS below it to profit on advertised sales.
What is the difference between ACOS and ROAS?
They are the same thing inverted. ACOS (advertising cost of sale) is ad spend ÷ ad sales, as a percentage — lower is better. ROAS (return on ad spend) is ad sales ÷ ad spend, as a multiple — higher is better. A 25% ACOS is a 4× ROAS. Break-even ROAS is 1 ÷ break-even ACOS.
How do I find my 'profit before ads' number?
It is what one unit keeps after Amazon's referral and FBA fees and your product, shipping and other costs, but before any advertising. The FBA profit calculator works it out from your price, cost and fees; enter that figure here.
What target ACOS should I run?
It depends on your goal. Break-even ACOS is the ceiling — above it you lose money on each ad sale. To keep a set profit per unit, use the target ACOS this calculator shows: (profit before ads − your target profit) ÷ price. For a launch you might run close to break-even to win rank; for a mature product you run below it to bank profit.
Does this send my numbers anywhere?
No. The calculation runs entirely in your browser — nothing you type is sent to us or any server. Only the early-access email leaves your browser, if you choose to join the list.
Related free tools
- FBA profit & break-even calculator — net profit, margin and ROI, and the profit-before-ads number this page needs.
- Settlement report analyser — reconcile a real payout and see per-SKU profit from your own report.
- Reorder-point & safety-stock calculator — when to send your next FBA shipment and how many units.
- Where is my FBA stock, and what does it trigger? — which states want you registered for sales tax.
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