Amazon FBA Calculator

What this calculator does

Selling on Amazon looks simple until the fees arrive. The referral fee takes a percentage of your sale price, FBA charges a fulfilment fee per unit, and storage ticks away every month. This calculator puts all three in one place so you can see your real profit per unit — not the number you hope for, the number you actually keep.

How the numbers work

Amazon's referral fee is a percentage of the sale price and depends on the category — most categories sit between 8% and 15%, and the default here is 15%. The FBA fulfilment fee depends on the size tier and weight of your product; a small standard item is roughly $3.50 to $5.00. Storage is charged per cubic foot per month and rises sharply in the fourth quarter, so the per-unit storage figure here is one you estimate from your own product dimensions. Profit per unit is the sale price minus product cost, inbound shipping, referral fee, fulfilment fee, storage and any other per-unit cost. The break-even price is the lowest price at which you make exactly nothing — anything below it loses money on every sale.

How to use it

Start with the price you actually plan to charge, not the price you wish the market would accept. Enter your landed product cost — factory price plus freight, duties and prep, not just the unit price on the invoice. Add inbound shipping per unit, set the referral percentage for your category, and enter the FBA fee for your size tier. If you sell 100 units a month, the monthly profit line tells you whether the listing is worth the management time.

Common mistakes

The most expensive mistake is forgetting the referral fee is charged on the full sale price, including shipping the buyer pays. The second is pricing from the FBA fee of a smaller size tier than your product ships in — measure the packaged product, not the product. The third is ignoring storage: slow-moving stock in Q4 can quietly eat the margin of your best sellers. Re-run the numbers every time Amazon announces a fee change, and again before any big inventory order.

Frequently asked questions

What is a good profit margin for Amazon FBA?

Most sustainable private-label sellers aim for 25–40% net margin per unit after all Amazon fees, product cost and shipping. Below 15% the business is fragile: one fee increase or one returns spike can wipe it out. Use the margin line above as your first filter — if a product cannot clear 20% at a realistic price, it is usually not worth listing.

How much is the Amazon referral fee?

It depends on the category. Most categories charge 8–15% of the sale price, with a minimum fee per item. Some categories, such as consumer electronics, are lower; others, such as clothing accessories, are higher. The default in this calculator is 15% — change it to your category's published rate for an accurate result.

Does this calculator include PPC advertising costs?

No. Advertising is deliberately left out because it varies so much by keyword and category. Treat the profit per unit here as your profit before ads, then subtract your target advertising cost of sale (ACOS). If you spend 10% of revenue on ads, subtract 10 points from the margin above.