How marketplace fees affect profit
Marketplace fees are usually calculated from more than the item price. Many platforms charge their percentage on the order total, which can include shipping paid by the buyer. That means free shipping and paid shipping need to be compared carefully. A seller may feel like shipping is separate, but the platform may still treat the collected shipping amount as part of the feeable transaction.
Use this calculator to separate percentage fees from fixed fees. A percentage fee grows with price. A fixed fee hurts low-priced items more because it takes the same amount from every order. A 30 cent fixed fee is small on a 100 dollar order, but it is large on a 4 dollar accessory.
The effective fee rate shows total fees as a share of the order total. It is often higher than the advertised marketplace percentage because it includes payment processing and fixed charges. Use it as a quick comparison when deciding where a product should be listed.