What makes this a fair comparison?
The tool holds the selling price, product cost, packaging, labor, and other per-sale costs constant. Etsy and eBay use the entered postage because the seller normally fulfills those orders. Amazon uses its FBA fulfillment fee instead, plus your inbound, storage, returns, and advertising allowances.
Free-shipping comparison: the same selling price is used on all three marketplaces and no separate shipping charge is collected from the buyer. If your Etsy or eBay listing charges shipping separately, use the detailed marketplace calculator.
The fee pattern on each marketplace
| Marketplace | Main fee pattern | Cost sellers often miss |
|---|---|---|
| Amazon FBA | Referral + size/weight fulfillment | Inbound, storage, ads, returns, and measured size tier |
| Etsy | Listing + transaction + payment processing | Offsite Ads, labor, and real postage |
| eBay | Final value + per-order fee | Buyer tax in the fee base, promotion, and postage |
Profit per sale is not the whole channel decision
A marketplace with lower modeled profit can still win if it produces a higher selling price, stronger conversion, or more sales. Product eligibility matters too: Etsy is not a general marketplace for every mass-produced item. Use the result to choose what deserves deeper testing, not to predict demand.
How to stress-test a product
Run an expected case and then a conservative case. Raise postage, advertising, labor, and return allowances. Select the applicable Etsy Offsite Ads rate and a realistic eBay promotion. A product that remains profitable under the conservative case is safer than one that works only when every assumption is optimistic.
Marketplace comparison FAQ
Why is buyer sales tax included?
Etsy’s US payment-processing fee can include applicable tax in the payment total, while eBay calculates its standard final value fee on the total amount of the sale including sales tax. Amazon’s referral estimate here uses the entered item price.
Why does Amazon ignore my postage input?
Amazon FBA charges a fulfillment fee based on the product’s tier and shipping weight. The seller-paid postage field is used only for Etsy and eBay in this comparison.
Does the highest profit mean I should list there?
No. Check eligibility, competition, achievable price, conversion, return behavior, and operational workload. The comparison isolates unit economics; it does not estimate demand.
Does this include every marketplace exception?
No. It models common US assumptions: non-apparel Amazon FBA, US Etsy Payments, and an eBay seller without a Store in a common 13.6% category. Use each detailed calculator and the marketplace’s official tools before committing inventory.