Amazon FBA Profit Calculator

What do I actually keep per unit after Amazon takes its cut?

Your numbers

Result

Net profit per unit

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How this is calculated

Amazon's fees are deducted in several separate places, which is why a product that looks profitable on a spreadsheet often is not. This calculator adds the referral fee, the FBA fulfilment fee, storage, inbound shipping and your advertising cost per unit, then subtracts all of it from the selling price.

Real example: Bluetooth earbuds

Selling price $29.99, COGS $7.50, inbound $1.20/unit, referral 15%, FBA $5.75, storage $0.35, other $0.50, ads $2.50/unit.

Result: Amazon takes $10.50 (35%), total cost $17.25, net profit $8.49 per unit at 28% margin. Break-even price: $19.71.

Referral fee = selling price × referral rate
Amazon fees = referral fee + FBA fulfilment fee + storage + inbound shipping
Total cost per unit = COGS + Amazon fees + other costs + advertising cost
Net profit per unit = selling price − total cost per unit
Break-even price = (COGS + other + ads + FBA + storage + inbound) ÷ (1 − referral rate)

What to make of the number

A net margin under 10% on FBA leaves almost nothing for the mistakes that will definitely happen — a bad batch, a storage surcharge, a price war. Most private-label sellers who last are running 15–25% net after ads, and they get there by cutting unit cost or raising price, not by shaving ad spend.

Frequently asked questions

What is a good net margin for an Amazon FBA product?

Aim for 15–25% net profit after every fee and after advertising. Below 10% the business cannot absorb a supplier price increase, a storage surcharge or a competitor undercutting you, and there is no cash left to fund the next product launch.

Is the referral fee calculated on the item price or the total order?

On the total price the buyer pays for the item including shipping and gift wrap, excluding tax. It is not calculated on your cost. A per-item minimum referral fee also applies in many categories, usually around $0.30.

Why does my actual profit differ from the estimate?

Mostly because of size tier changes, peak-season storage rates, aged-inventory surcharges and returns. Also check that your inbound freight figure is per-unit and not per-shipment — that single error is the most common reason estimates look optimistic.

Should I include advertising in unit economics?

Yes, but split it. Keep an ad-inclusive number to judge whether the product is viable at current efficiency, and an ad-free number to see what the product earns once it ranks organically. Scaling a product that only works at zero ad spend is a trap.

How often do Amazon fee rates change?

Referral rates are fairly stable, but fulfilment fees and storage rates are revised annually and there is usually an October–January peak-season surcharge. Re-check the rate card at the start of Q4 rather than assuming last year's numbers still hold.

What is the break-even price and how do I use it?

Break-even price is the minimum selling price where profit equals zero. If your current selling price is below this figure, you are losing money on every sale. Use it as a floor, not a target.

How do returns affect my real profit?

Returns erase profit and add costs. A 10% return rate on a 15% margin product turns most sales unprofitable. Always budget a returns percentage based on your category history, not your best case.

When should I switch from FBA to FBM?

FBA makes sense when volume justifies storage fees and you need Prime eligibility. FBM can be cheaper for heavy, slow-moving, or low-margin items where fulfilment fees eat the profit.

Do the research before you commit inventory

SkuMath shows you the math. Helium 10 supplies the live Amazon data those calculations need as inputs — product demand, keyword volume, competitor reviews and profit tracking.

Try Helium 10 free