Methodology, sources & editorial standards

We begin with costs you control: materials, packaging, labor, shipping paid by the seller, overhead, miscellaneous costs, advertising cost per sale, and a return allowance. Labor is calculated as hours multiplied by the hourly rate you enter.

If the buyer pays shipping, that charge is included when percentage-based marketplace fees are calculated. The calculator then subtracts buyer-paid shipping from the item price it recommends. This avoids the common error of adding a fee percentage on top of a target amount and then paying the same percentage on the increase.

Defaults are starting points, not universal rates. Payment processing varies by country, plan, card type, sales channel, and account. Regional regulatory fees and taxes are not automatically inferred. Every fee field remains editable so you can replace our example with the rate shown in your own seller account.

Product-price examples in our guides are illustrative scenarios, not market-price promises. Your materials, positioning, customer, taxes, demand, and production capacity can justify a very different result.

Formula tests cover labor, base costs, fixed and percentage fees, reverse pricing, target margins, psychological rounding, discounts, and craft-fair break-even scenarios. Before publishing a rate change, we compare it with a primary source and run the project's automated checks.

If a rate or result looks wrong, email us with the scenario and a link to the relevant platform documentation. We verify corrections before changing defaults and update the review date when a substantive editorial or fee review is completed.