Amazon FBA Fee Calculator
Enter your selling price and costs to see exactly what Amazon takes and what you keep. Unlike the official calculator, this one includes advertising spend and returns — the two costs that quietly turn a "profitable" product into a losing one.
What this calculator includes that others don't
Amazon's own revenue calculator shows referral and fulfillment fees. That's useful, but it is not your profit. Two costs are missing from that view, and they are usually the two that decide whether a product is worth selling.
Advertising. Very few products get meaningful organic sales on Amazon without paid placement, particularly in the first six months. If you spend $3,000 on Sponsored Products and sell 1,000 units, your real cost per unit is $3 higher than the official calculator suggests. Enter that number in the advertising field.
Returns. A returned unit costs you more than the refund. You lose the landed cost of the goods and the fulfillment fee you already paid, and returned inventory often cannot be resold at full price. This calculator applies your expected return rate against those costs rather than pretending returns are free.
How each fee works
Referral fee. Amazon's commission on the sale price. Most categories are 15%. Consumer electronics, computers, cameras, and video games are 8%. Amazon device accessories are 45%. There is a $0.30 minimum on most categories, which is why very cheap items have worse unit economics than the percentage alone suggests.
FBA fulfillment fee. A flat per-unit charge based on size tier and weight, covering pick, pack, and shipping. This is a step function, not a smooth curve — a product that is one ounce over a tier boundary costs meaningfully more to fulfill than one just under it. If your product sits near a boundary, shaving packaging weight is often the highest-return optimization available.
Storage. Charged monthly per cubic foot, with higher rates in Q4 and surcharges on inventory held over 181 days. Divide your monthly storage bill by units on hand to get the per-unit figure.
Reading the three profitability numbers
The calculator returns net profit, margin, and ROI, and they answer different questions.
Net profit per unit tells you what a single sale is worth. Useful for deciding whether a product is worth the operational overhead at all.
Net margin is net profit divided by selling price. It tells you how much cushion you have. A product at 8% margin gets wiped out by a single fee increase or a competitor undercutting you by a dollar. Most experienced sellers treat 15% as a floor and target 25–30%.
Return on investment is net profit divided by the cash you actually tie up per unit. This is the number that matters most when capital is your constraint rather than shelf space. A product with a 20% margin but a 100% ROI turns your money over far faster than one with a 35% margin and a 40% ROI. If you are self-funded, optimize for ROI.
Break-even price
The break-even output shows the lowest price at which you do not lose money. Because the referral fee is a percentage, you cannot simply add your costs together — dropping your price also drops the fee, so the calculation has to solve for it. Knowing this number is what lets you respond to a price war without accidentally selling below cost.
A note on fee accuracy
The size-tier presets in this calculator are approximations for US marketplace standard sizes. Amazon revises its fee schedule at least annually and applies surcharges that vary by season and by fulfillment center. Before committing to a product, pull the exact fulfillment fee for your ASIN from Seller Central and enter it using the "Custom" size tier. Treat the presets as a screening tool for evaluating many products quickly, not as a final number for a purchase order.
Frequently asked questions
What is a good profit margin for Amazon FBA?
Most sellers target 25–30% net margin after all fees, advertising, and returns. Below 15% you have very little room to absorb a fee increase or a competitor undercutting your price. If you are cash-constrained, return on investment matters more than margin — a 20% margin product that turns over quickly can build capital faster than a 35% margin product that sits.
Does this calculator include Amazon advertising costs?
Yes. Amazon's official revenue calculator does not, which is the single biggest reason sellers overestimate profitability. Divide your total ad spend for a period by the units sold in that period and enter the result.
What is the difference between margin and ROI?
Margin is net profit divided by the selling price — it measures pricing cushion. ROI is net profit divided by the cash you invested per unit — it measures how efficiently your capital works. A product can have a strong margin and a weak ROI if the goods are expensive, and vice versa.
How accurate are the fulfillment fee presets?
They are approximations for US standard size tiers and are useful for quickly screening many product ideas. Amazon revises fees at least annually and adds seasonal surcharges, so pull the exact figure for your specific ASIN from Seller Central and use the Custom size tier before making a purchase decision.
Why is my break-even price higher than my costs added together?
Because the referral fee is a percentage of whatever you charge. Lowering your price lowers the fee too, so the break-even point has to be solved for rather than summed. The calculator does this for you.