Amazon FBA Profit Calculator
Work out profit per unit before you commit money to inventory — including the fees that only show up after your stock is already in Amazon's warehouse.
Result
$0.00
Where the money goes
Saving keeps your figures on this device only — nothing is sent anywhere.
Why the referral fee field is editable and defaults are dangerous
The number that decides whether to buy stock: ROI
Margin tells you how healthy each sale is. ROI tells you whether the inventory is worth buying, because it measures profit against the cash you had to put in and get back before you can reorder:
ROI % = (Profit per unit ÷ Unit cost including inbound) × 100
With the defaults, a $24.99 product costing $7.20 landed returns roughly $9.30 profit — about a 129% ROI. That means every dollar of stock returns itself plus a bit more each cycle, which is what makes reordering possible without new money. A 15% ROI product can still show a "positive" profit and still slowly starve your cash, because you wait weeks to get your money back for very little gain.
Fees that catch new FBA sellers
- Fulfilment fee scales with size and weight tier, not price. A bulky $12 item can be structurally unprofitable no matter how well it sells — the fee does not shrink because your margin is thin.
- Storage is charged on stock that has not sold. Slow sellers pay rent for the privilege. Spread your storage estimate across units you realistically sell per month, not units you own.
- Returns. A category with a 10% return rate effectively removes 10% of your unit profit. Add it into the "unit cost" field as a rough loading if your category is returns-heavy.
Before you place a supplier order
Run three scenarios in the calculator, not one: your expected price, your expected price minus 15% (because you will end up discounting), and your unit cost plus 20% (because freight and duty surprise everyone). If profit survives all three, the product is robust. If it only works in the best case, it is a gamble with your own cash.
Questions
What referral fee percentage should I enter?
The one for your product's own fee category, taken from Seller Central. Amazon lists category-specific rates and price-tier exceptions rather than one universal percentage, so any single figure quoted for 'all products' is an approximation.
What is a good ROI for Amazon FBA?
Rather than a fixed target, judge it against your cash cycle: the money is locked up from paying the supplier until Amazon pays out. A higher ROI means the same money can be reinvested more times per year, which matters far more than margin percentage when you are starting with little capital.
Does this include Amazon's monthly subscription fee?
No — that is a fixed business cost, not a per-unit one. Put it into the break-even calculator as a fixed cost instead, which will tell you how many units you need to sell to cover it.