How to calculate real profit per ASIN on Amazon
Amazon tells you what you sold. It doesn't tell you what you kept. Here's the formula, and where every number hides.
Short answer
Profit per ASIN is sales minus Amazon referral fees, FBA fulfillment fees, storage fees, ad spend, refund costs, other Amazon fees and your cost of goods. Fees and refunds come from settlement and transaction data, storage from the monthly storage fee report, ad spend from the Sponsored Products advertised product report, and COGS from your own records.
On this page
The formula
Profit per ASIN = sales − referral fees − FBA fulfillment fees − storage fees − ad spend − refund costs − other Amazon fees − cost of goods
Every term is per ASIN, for the same period. Most “profit” numbers you see skip at least two of them. Usually storage and refunds, sometimes ads.
Where $10,000 of sales actually goes
Example product, one month
- Sales and what’s left
- Costs
View as table
| Line | Amount |
|---|---|
| Sales | $10,000 |
| Amazon fees | −$3,050 |
| Ads | −$1,900 |
| Refunds | −$620 |
| Storage | −$430 |
| Before COGS | $4,000 |
In that example, $10,000 of sales leaves $4,000 before cost of goods. If the goods and shipping to Amazon cost $2,500, real profit is $1,500: a 15% margin on a product that looked like it was printing money.
Where each number lives
| Line | What it is | Where to find it |
|---|---|---|
| Sales | What shoppers paid for the product, before Amazon takes anything | Settlement reports, the Payments transaction view, or the sales and traffic report |
| Referral fees | Amazon's commission, a percentage of the sale price. For most categories between 8% and 15% | Settlement and transaction data, per order item |
| FBA fulfillment fees | Pick, pack and ship, per unit, set by size tier and weight | Settlement and transaction data; the FBA fee preview report for estimates |
| Storage fees | Monthly charge for space in Amazon's warehouses, higher from October to December | The monthly storage fees report, per ASIN |
| Ad spend | What you paid for ads promoting this ASIN | The Sponsored Products advertised product report |
| Refund costs | The refunded sale, minus the referral fee Amazon gives back, plus the refund administration fee | Settlement and transaction data |
| Other Amazon fees | Coupons, deals, inbound placement, aged inventory surcharges and similar | Settlement and transaction data |
| Cost of goods | What you paid for the product and to get it to Amazon | Your own records. Amazon doesn't know it |
The three that get skipped
Storage
Storage is billed for the whole account, so it never shows up on an order. The monthly storage fees report breaks it out per ASIN. Watch the last quarter of the year, when monthly rates go up, and inventory that sits long enough to pick up aged inventory surcharges. A slow ASIN can look profitable per sale and still lose money on the shelf.
Refunds
A refund costs more than the sale. Amazon returns most of the referral fee but keeps a refund administration fee: the lesser of $5.00 or 20% of the referral fee. You also lose the FBA fee on the original shipment, and a returned unit may not be sellable again. Compare refunds per ASIN, not per account. One product with a sizing problem can drag down the whole catalog.
Ads
Ad spend for Sponsored Products comes per advertised ASIN in the advertised product report, which makes it easy to assign. Ads that promote several products at once, like Sponsored Brands, need a split: by each ASIN's share of the attributed sales is the simplest fair rule.
Two ratios worth tracking
| Ratio | Formula | Tells you |
|---|---|---|
| Margin | Profit ÷ sales | How much of each dollar you keep |
| TACoS | Ad spend ÷ total sales | How dependent the product is on ads. Falling TACoS while sales grow usually means organic sales are picking up |
Use margin before ads to set your break-even ACoS for each ASIN. Finding wasted ad spend shows how.
Why sales don't match your payout
Amazon pays out on settlement periods, usually about every two weeks, and each payout nets fees, refunds, reserves and adjustments from orders in different weeks. That's why the money that arrives never matches what you sold that week. For profit, match fees and refunds to the orders they belong to, not to the day they were paid.
Doing it without a spreadsheet
The math is simple. Collecting the inputs is the hard part: four reports, two APIs and a cost sheet. Connected to both the Selling Partner API and the Amazon Ads API, an AI app can pull them in one go:
Ask your AI
Calculate profit per ASIN for September in the US marketplace: sales, referral fees, FBA fees, storage, ad spend, refunds and other fees. Use my COGS from this table. Sort by profit, lowest first.
Frequently asked questions
Does Seller Central show profit per ASIN?
Seller Central shows the pieces in different reports, but Amazon doesn't know your cost of goods, so any number it shows stops short of real profit. You need to add COGS and allocate account-level costs like storage yourself.
What is a good profit margin on Amazon?
It depends on the category, price and how much the product relies on ads. The useful question is whether each ASIN's margin covers its ad spend and still leaves enough to reinvest. Track margin and TACoS per ASIN, not just for the account.
How much is the Amazon refund administration fee?
In the US, the refund administration fee is the lesser of $5.00 or 20% of the referral fee on the refunded item. Amazon keeps it when it refunds the rest of the referral fee.
How often should I calculate profit per ASIN?
Monthly at minimum, and weekly for your top sellers and anything you're advertising heavily. Fee changes, storage rates and ad costs move during the year, especially in the fourth quarter.