Every commission rate, flat fee, payment-processing charge, and shipping assumption in the calculator and the guides is taken from the marketplace's own published seller documentation — help centre pages, fee schedules, and category-specific rate tables. We do not take figures from affiliate marketing blogs or from other fee calculators, because those are frequently out of date by a year or more.

The written guidance and the calculator share a single set of numbers, so an article can never quote a rate the tool does not use.

Fee structures are reviewed monthly, and immediately whenever a marketplace announces a change. Each guide shows the month it was last reviewed. Where a platform has category-dependent rates or promotional discounts, we say so rather than presenting a single headline percentage as the whole story.

Estimates are labelled as estimates. We deliberately do not claim a payout is exact, because tax handling, category variation, store subscriptions, and promotions all move the real number.

The guides are written and maintained in-house by the people who build SellWhere. We are resellers and software makers, not a content agency, and we do not publish sponsored rankings or paid placements. No marketplace pays us for a higher position or a more favourable write-up.

Some articles use AI tools for drafting and for checking arithmetic. Every figure is verified against the platform's published documentation before an article is published, and the final editorial decision on what gets published is human.

SellWhere is free to use and supported by advertising. Advertisements are kept out of the comparison form and away from interactive controls so they cannot be mistaken for part of the tool. Advertising has no influence on which platform we recommend for a given item — the ranking is arithmetic, based on the net proceeds after fees and shipping.

If a fee has changed and we have not caught it, we want to know. Send the platform, the figure we show, and the page where the current rate appears through the contact form, and we will correct the calculator and the affected guides together. Substantive corrections are reflected in the review date shown on the article.