Amazon ACoS Calculator & Break-Even Guide
Advertising Cost of Sale (ACoS) is one of the most important metrics for Amazon sellers. It is the share of sales revenue you spend on Amazon PPC. A "good" ACoS depends entirely on your product's margin structure — here is how to calculate it, find your break-even point, and see when PPC actually turns unprofitable.
What is ACoS?
ACoS is calculated using a simple formula:
ACoS = (Total Ad Spend ÷ Total Sales) × 100%
Example: If you spend $200 on ads and generate $1,000 in sales:
ACoS = ($200 ÷ $1,000) × 100% = 20%Break-even ACoS formula
Your break-even ACoS is the maximum you can spend on advertising before PPC sales stop contributing profit. It equals your pre-advertising gross margin percentage:
Break-Even ACoS = Gross Margin %
Gross Margin % = (Selling Price − COGS − Fulfillment − Referral − Other) ÷ Selling Price × 100%| Pre-ad gross margin | Break-even ACoS | Spend above this is unprofitable |
|---|---|---|
| 50% | 50% | >50% |
| 44% | 44% | >44% |
| 35% | 35% | >35% |
| 25% | 25% | >25% |
| 15% | 15% | >15% |
In practice, target an ACoS well below break-even to leave room for returns (5–10%), storage and unexpected costs. A healthy target is break-even ACoS minus 10–15 percentage points.
Worked example: kitchen gadgets at a 22% ACoS
Using SellerElf's kitchen-gadgets defaults at a $24.99 selling price: landed product cost $4.60, FBA fulfillment $5.61 and a 15% referral fee of $3.75. That leaves a pre-ad gross profit of $11.03, or a 44.1% gross margin — so break-even ACoS is 44.1%.
| Line | Per unit |
|---|---|
| Selling price | $24.99 |
| Landed cost | $4.60 |
| FBA fulfillment | $5.61 |
| Referral fee (15%) | $3.75 |
| Pre-ad gross profit | $11.03 (44.1%) |
| Advertising at 22% ACoS | $5.50 |
| Return loss (7%) | $0.77 |
| Net profit | $4.52 (18.10%) |
| Break-even ACoS | 44.1% |
The takeaway: kitchen gadgets can absorb a 22% ACoS because break-even is 44.1%. Categories with thinner gross margins — phone cases or LED lights — have far less headroom, which is why the same ACoS can be profitable in one category and ruinous in another.
Check your own break-even ACoS
Enter your price, landed cost and fulfillment mode in the free calculator. It returns gross margin, net margin and the ad cost at your target ACoS, so you can see exactly how much PPC room you have before the sale stops paying.
ACoS profitability by category
| Category | Typical ACoS | Break-Even ACoS | Net Margin at Typical ACoS |
|---|---|---|---|
| Board Games | 15% | 38% | 23% |
| Pet Supplies | 20% | 35% | 15% |
| Yoga Mats | 18% | 32% | 14% |
| Phone Cases | 25% | 28% | 3% |
| Wireless Earbuds | 20% | 30% | 10% |
| LED Lights | 28% | 25% | -3% (loss) |
| Screen Protectors | 30% | 20% | -10% (loss) |
Some competitive categories (phone cases, LED lights, screen protectors) have typical ACoS levels that approach or exceed break-even. That is why many sellers in those categories lose money on PPC-attributed sales.
How organic sales reduce effective ACoS
Your reported campaign ACoS only counts PPC-attributed sales. If organic sales are 70% of your volume, your effective ACoS across all sales is far lower:
Reported ACoS: 25% (from PPC campaign data)
PPC share of total sales: 30%
Organic share: 70%
Effective ACoS = 25% × 30% = 7.5%
Your true advertising cost across ALL sales is only 7.5%.This is why established products with strong organic rankings can sustain higher PPC bids — their effective ACoS across total volume stays healthy even when the campaign ACoS looks high.
ACoS vs TACoS
What is the difference between ACoS and TACoS?
ACoS is ad spend divided by PPC-attributed sales only. TACoS (total advertising cost of sale) is ad spend divided by total sales, including organic. TACoS therefore falls as organic rank improves, and it is the better measure of whether advertising is building the listing.
Which should I optimize — ACoS or TACoS?
Use ACoS to judge individual campaigns and break-even, and TACoS to judge overall listing health. A rising TACoS with flat sales means advertising is not compounding into organic rank; a falling TACoS means it is.
Can ACoS be higher than TACoS?
Yes, and it normally is. Because ACoS ignores organic sales, it is usually higher than TACoS for a listing with meaningful organic demand. Compare the two together rather than in isolation.
See the math on real categories
Figures use SellerElf category defaults and are as of 2026-10-02. Model your own inputs in the calculator for exact numbers.