FBA Profit Calculator
Per-unit net profit, margin, ROI, and breakeven ACOS for Amazon sellers. Records are saved in this browser.
Results (per unit)
Breakeven ACOS is the ad spend (as % of price) at which net profit hits exactly $0 - bid above it and every sale loses money.
How this FBA profit calculator works
Amazon takes its cut in several separate places, which is why a product that looks profitable on the supplier invoice can still lose money after it ships. This calculator pulls every per-unit cost into one view so you can see the real number before you commit to an order.
Nothing is estimated on your behalf. You enter your own costs and fee rates, and the page recalculates as you type.
The formulas
Landed cost = supplier unit price + first-leg freight + prep & labeling
Operational cost = referral fee + FBA fulfillment fee + storage + advertising + return reserve
Net profit = retail price − landed cost − operational cost
Net margin = net profit ÷ retail price
ROI = net profit ÷ landed cost
Breakeven ACOS = profit before ad spend ÷ retail price
What each input means
- Retail price
- What the customer pays, before tax.
- Supplier unit price
- What you pay the factory per unit, excluding shipping.
- First-leg freight
- Getting the goods from the supplier into an Amazon fulfillment center, divided across the units in the shipment. The shipment helper converts a freight invoice, duty, and other fees into this per-unit number.
- Prep, labeling & packaging
- Polybagging, FNSKU labels, bundling, and anything your prep center charges.
- Referral fee
- Amazon's commission, charged as a percentage of the retail price. Most categories sit at 15%, but it varies — see the full Amazon FBA fee tables for your category.
- FBA fulfillment fee
- The per-unit pick, pack, and ship charge, set by the product's size tier and weight. Don't know yours? The FBA fee calculator looks it up from Amazon's current rate card.
- Storage fee
- Monthly warehouse storage, spread across the units you expect to sell.
- Advertising
- Either your ACOS as a percentage of the retail price, or a flat ad spend per unit.
- Return & damage reserve
- Money set aside for refunds, unsellable returns, and damage. Entering this as a percentage of price is usually closer to reality than a flat figure.
Frequently asked questions
How do you calculate FBA profit per unit?
Start with the retail price, subtract the landed cost of the unit (supplier price, first-leg freight, and prep), then subtract every Amazon-side cost: the referral fee, the FBA fulfillment fee, storage, advertising, and a reserve for returns. What is left is your per-unit net profit.
What is a good profit margin for Amazon FBA?
Most established FBA sellers aim for a net margin somewhere between 15% and 30% after all fees and advertising. Below roughly 10% you have very little room for a fee increase, a price war, or a bad returns month. Margin alone does not tell the whole story, though, because it ignores how much cash you had to tie up to earn it. For the full picture — benchmarks, failure modes, and a pre-purchase checklist — see is Amazon FBA profitable in 2026?
Why is my ROI different from my profit margin?
They measure against different things. Margin divides profit by the retail price and answers "how much of each sale do I keep?" ROI divides profit by your landed cost and answers "how hard is my cash working?" A cheap product can post a modest margin and still show excellent ROI, which matters when your capital, not shelf space, is the constraint on growth. To go deeper — including annualizing ROI by your inventory turns — use the FBA ROI calculator.
What is breakeven ACOS and how is it calculated?
Breakeven ACOS is the most you can spend on advertising, as a percentage of the retail price, before the sale stops making money. It is your profit before ad spend divided by the retail price. Spend under it and the sale is profitable; spend over it and you are buying revenue at a loss. It is the number to check before raising bids.
Does this calculator use current Amazon fee rates?
No, and that is deliberate. Referral percentages, fulfillment fees, and storage rates change over time and vary by category, size tier, and season. You enter your own figures, taken from Seller Central for your specific product, so the result reflects what Amazon actually charges you rather than a generic table that quietly goes stale. For a dated reference of the current rates, see our guide to Amazon FBA fees in 2026.
Does it handle returns and refunds?
Yes, through the return and damage reserve. Set it as a percentage of the retail price to model a typical return rate, or as a flat amount per unit. Categories like apparel carry far higher return rates than most, and ignoring that is one of the commonest ways a spreadsheet overstates profit.
Is my data saved or sent anywhere?
No. The calculator runs entirely in your browser, with no accounts and no server. Your saved records live in your browser's local storage and never leave your device. See the privacy policy for detail.
More FBA calculators & guides
Calculators
- FBA fee calculator — what Amazon charges per unit sold, computed from the current 2026 US rate cards.
- FBA ROI calculator — return on every dollar of inventory, per unit and annualized by your turns.
- FBA vs FBM calculator — both routes modeled per unit and per month, including labor and the Prime badge's conversion lift, with a breakeven verdict.
Guides
- Amazon FBA fees in 2026 — every fee with current rates: referral by category, fulfillment by size tier, storage, and the surcharges that catch sellers out.
- Is Amazon FBA profitable in 2026? — the honest unit economics: benchmarks, the five ways sellers lose money, and a pre-purchase checklist.
- How does Amazon FBA work? — what FBA means, the five-step loop, FBA vs FBM, and how to start without losing money.
Helper tools
Separate from the profit math above. The first two read your cost inputs live.
Price finder - what should I charge?
Breakeven is your floor - the lowest promo price that still doesn't lose money.
Shipment → landed cost per unit
ACOS ↔ ROAS converter
The two are reciprocals. Edit either one and the other follows.