Amazon FBA Profit Calculator
Calculate true per-unit profit after every Amazon fee, PPC cost, and return loss. The number you actually keep.
Per-unit inputs
An unsellable return costs you the whole landed cost. This drives the return loss far more than the sale price does.
Net profit per unit
$7.91
Healthy
Margin %
26.39%
Profit ÷ sale price
ROI %
83.31%
Profit ÷ landed cost — for capital recycling
Breakeven ACOS
34.73%
Ad spend as a share of sales, at zero profit
Cost per return
$10.90
Fulfilment + admin fee + unsellable stock
Cost breakdown
Analysis & insights
On a $29.99 sale price, your net profit per unit: $7.91 (26.4% margin, 83.3% ROI on COGS). Strong economics. Reinvest in PPC scaling or product variations to compound the advantage.
Healthy margin
Strong FBA margin — leaves room for absorbing fee increases and seasonal PPC spikes.
Risk & benchmark gauge
Current band
Healthy
26.4% margin
Industry benchmarks
- Profit per unit$7.91
- Margin %26.4%
- ROI on COGS83.3%
- FBA industry minimum15% margin / 30% ROI
- Investor target25%+ margin
Key insights
PPC is volatile — budget for 20-30% ACoS
New listings often need 30-50% ACoS to gain rank. Established listings can target 15-25%. Build PPC into your model permanently — it's not optional.
Returns hit hardest at premium-price items
Amazon's standard return rate is 5-10% across categories. Apparel and electronics can hit 20-30%. Even non-defective returns become unsellable and incur removal fees.
Long-term storage fees punish slow movers
Inventory aged 271+ days incurs $6.90/cubic-foot/month surcharges. Plan sell-through so seasonal items leave FBA before the next assessment.
Recommended actions(3)
Lower PPC ACoS to 20% or under
High priorityNegative-keyword pruning, exact-match shifts, and ASIN-targeting campaigns typically cut ACoS 5-10 points over 60 days. Single biggest profit lever for most FBA sellers.
Optimize for the lowest tier of FBA fee category
Medium priorityGoing from "Standard size large" to "Standard size medium" (often via packaging reduction) cuts fulfillment fee 15-25%. Worth re-engineering for high-volume products.
Build review velocity in the first 90 days
Medium priorityFirst-90-day reviews drive BSR (Best Sellers Rank) and conversion. Use Amazon Vine, Subscribe & Save, and email follow-ups (TOS-compliant) to compound.
Find the Best Personal Loan
* Partner links. CalcProLabs may earn a referral fee at no cost to you.
Related Calculators
This tool is for educational purposes only and does not constitute financial, tax, or investment advice. Consult a qualified financial professional for advice specific to your situation.
What is Amazon FBA Profit?
Amazon takes a larger share of a sale than most sellers expect, and it takes it in several separate pieces. The referral fee is a percentage of the sale price. The fulfilment fee is a flat charge by size and weight. Storage is monthly. Advertising is per click whether or not anything sells. Returns cost you even when the item comes back.
Add them together and a $29.99 product with $8 of goods behind it commonly nets under $8. That is a workable business, but it is not the margin the sale price suggests.
The two figures that actually govern decisions are net profit per unit and return on the landed cost of goods. The first tells you whether the product works; the second tells you how fast your capital recycles, which is what limits growth in a business where inventory is the constraint.
The formula — how to calculate Amazon FBA Profit
- Referral fee
- = 15% in most categories, 8% in some, up to 45% for Amazon device accessories
- Resellable %
- = the share of returns that come back in sellable condition; the rest cost you the whole landed cost
- Breakeven ACOS
- = the advertising cost of sale at which profit reaches zero — the ceiling on your ad bids
A return does not simply reverse a sale. The fulfilment fee is not refunded, Amazon retains a refund administration fee, and a proportion of returned units cannot be resold.
Step-by-step example
- 01A $29.99 product: $8 cost of goods, $1.50 inbound shipping, $5.25 FBA fee, 15% referral, $2.50 of PPC per unit, a 3% return rate, and half of returns coming back sellable.
- 02Landed cost: $9.50. Referral fee: $4.50.
- 03Cost of a single return: $5.25 fulfilment (not refunded) + $0.90 refund admin fee + $4.75 of unsellable stock = $10.90. At a 3% return rate that is $0.33 a unit.
- 04Total cost: $9.50 + $5.25 + $4.50 + $2.50 + $0.33 = $22.08.
- 05Net profit: $7.91 a unit. Margin 26.4%. ROI on landed cost 83.3%.
- 06Breakeven ACOS: ($7.91 + $2.50) ÷ $29.99 = 34.7%. Above that level of ad spend the product loses money on every unit it sells.
- 07Note the shape of it: Amazon takes $9.75 of the $29.99 in fees, the goods cost $9.50, advertising takes $2.50, and $7.91 reaches you. The single largest line is not your product.
The fees, and which ones move
Fee schedules change, typically once or twice a year, and rarely downward. A product with a thin margin can be pushed under water by a single fee revision, which is an argument for building in more headroom than the current numbers require.
Size tier is worth optimising deliberately. Shaving a fraction of an inch off packaging to drop a tier can save more per unit than a supplier negotiation, and it costs nothing recurring.
What comes out of a sale
| Fee | Typical size | Driven by |
|---|---|---|
| Referral fee | 8–15% of price | Category. Most are 15% |
| FBA fulfilment | $3–$8 for standard size | Size and weight, not price |
| Monthly storage | $0.75–$2.40 per cubic foot | Volume and season — Q4 rates are far higher |
| Long-term storage | Surcharge after 181 days | Slow-moving inventory |
| Advertising | Highly variable | Category competition |
| Returns processing | Category-dependent | Return rate and resellability |
The fulfilment fee depends on size and weight rather than price, which is why low-priced bulky items rarely work on FBA and small light items can be very profitable.
Why ROI matters more than margin here
Margin tells you how much of each sale you keep. ROI on landed cost tells you how hard your capital is working, and in an inventory business that is the binding constraint.
Consider two products. One has a 40% margin and takes six months to sell through. The other has a 20% margin and sells through in six weeks. The second returns your capital four times more often, so it generates far more annual profit from the same money.
This is why experienced sellers target ROI rather than margin, commonly looking for 50% or better on landed cost, and why they care so much about sell-through rate.
It is also why storage fees hurt more than their size suggests. Slow inventory does not merely accrue fees; it locks up capital that cannot buy the next order.
The practical test for a product is not "is the margin good" but "how many times a year does this money come back to me, and at what return each time".
- Landed cost —
- goods plus inbound shipping and duties — the capital actually laid out per unit.
- Sell-through rate —
- how quickly inventory clears. Governs how often your capital recycles.
- ACOS —
- advertising cost of sale: ad spend divided by attributed revenue. Compare against breakeven ACOS to see whether a campaign makes money.
- TACOS —
- total advertising cost of sale, against all revenue including organic. The figure that shows whether advertising is building a business or renting one.
- Buy Box —
- the default purchase option on a listing. Losing it collapses conversion, and it is what makes competing on a shared listing precarious.
Advertising, and the number that caps your bids
Breakeven ACOS is the most useful figure this calculator produces and the one most sellers cannot state for their own products.
It is the profit before advertising, expressed as a share of the sale price. In the example above the product makes $10.41 before ad spend, which on a $29.99 price is 34.7%. Spend more than that on advertising and every sale loses money.
That does not make 34.7% a target. Advertising at breakeven can be rational for a launch, where you are buying rank and reviews rather than profit, and irrational as a steady state.
The distinction that matters is between ACOS and TACOS. A product with a 30% ACOS on ad-driven sales but plenty of organic sales alongside might have a 10% TACOS, which is a healthy business. One where nearly every sale is advertised has ACOS and TACOS converging, which means the product does not sell on its own and the advertising is not building anything.
Watching TACOS fall over time is the signal that a launch has worked. Watching it stay flat is the signal to stop spending.
The costs that are not per unit
This calculator computes unit economics, which is necessary and not sufficient. Above it sit the costs that do not scale with a single sale: the $39.99 monthly professional selling plan, product photography, samples, inspection and testing, brand registry, software subscriptions, and the inventory you have to buy before earning anything. A product with $7.91 of unit profit needs to sell a meaningful volume before any of that is recovered.
What actually goes wrong
The failure modes are consistent and mostly predictable.
Underestimating advertising is the most common. New products need aggressive spend to gain visibility, and the cost per click in competitive categories has risen steadily. A launch budget that assumes launch-day organic sales is a launch budget that fails.
Inventory timing is the second. Run out and you lose your ranking, which is expensive to rebuild. Order too much and capital sits in a warehouse accruing storage fees. Lead times from overseas manufacturing make this genuinely difficult to get right, and it is where most working capital is lost.
Competition on price is the third. A product that works at $29.99 does not work at $24.99, and a well-funded competitor can force that. Products without a real differentiator are one aggressive entrant away from unviable.
Then account risk, which is uniquely severe here. A suspension for a policy issue, an intellectual property complaint or a listing hijack can remove your entire revenue with no notice and a slow appeals process. Sellers concentrated on a single marketplace are exposed in a way that has no equivalent in most businesses.
The defence against all of these is margin. A product netting 30% survives a fee increase, a price war and a bad quarter. One netting 8% survives none of them.
Common mistakes to avoid
- Modelling a return as a fraction of the sale price. It costs the fulfilment fee, the admin fee and any unsellable stock.
- Measuring ROI against the product cost alone, leaving out inbound shipping.
- Ignoring storage fees, and long-term storage surcharges on slow inventory.
- Not knowing your breakeven ACOS, which is the ceiling on every ad bid.
- Confusing ACOS with TACOS, and missing that the product never sells organically.
- Optimising margin while ignoring sell-through, which is what governs capital recycling.
- Forgetting the fixed costs — selling plan, photography, samples, software — that unit economics do not include.
- Building a business on a product with no differentiator and a single competitor away from a price war.
Frequently asked questions
Sources & references
Written and fact-checked by the CalcProLabs Editorial Team. Read our calculation methodology and editorial policy.
Last updated