How to calculate your real Amazon FBA margin (with example)
The mistake that loses the most money on Amazon FBA is confusing selling price with profit. A $30 product can net you $2… or lose you money. In this guide you'll learn to calculate your real net margin with a concrete example.
The costs you must subtract
- Product cost — what you pay the supplier (usually 25-55% of the selling price depending on category).
- Amazon referral fee — usually ~15% of the selling price.
- FBA fee — handling, packing and shipping to the customer (varies by size/weight, ~$3-6 for small items).
- Shipping to Amazon — from the supplier to Amazon's warehouse.
- Advertising (PPC) — cost per sale to get visibility.
Step-by-step example
A product selling at $29.99:
| Selling price | $29.99 |
| Product cost (≈30%) | −$9.00 |
| Amazon referral fee (15%) | −$4.50 |
| FBA fee | −$4.50 |
| Shipping to Amazon (per unit) | −$1.00 |
| Advertising per sale | −$3.00 |
| Net profit | $7.99 (≈27%) |
A net margin of 27% is healthy. As a rule: below 20% the product is risky; above 30% it's excellent.
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The trick: calculate the margin BEFORE you fall in love
Many sellers calculate the margin after they've already bought inventory. Do it the other way around: filter by margin first and only then evaluate the rest. A pretty product with a 12% margin is not a business.
How WinnerFinder calculates the margin for you
WinnerFinder automatically estimates the cost by category, subtracts the fees and shows you the net margin of each product alongside its opportunity score — so you can filter by profitability in seconds, no spreadsheets.
Filter products by real margin
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