How we verify seller fees

SellerFees is an independent project by Rocky Panda. We are not affiliated with any marketplace.

Sources

Every number comes from the platform's own published US fee page or help-center article. Each calculator links to its exact source.

Daily checks

Once a day we check every source page for changes. If a page changes, that platform is flagged and a warning appears on its calculator until we re-verify the numbers. If a platform hasn't been verified for more than 7 days, its calculator shows a warning automatically.

Tested against official examples

Where platforms publish worked fee examples (for example, eBay's), our calculator is tested against them. The site is not published if any test fails.

Limitations

Calculators cover standard US fees. Promotions, account-specific discounts, store subscriptions and some categories are not included; each page lists what's not covered. Results are estimates. Rounding may differ by a cent.

Contact

Spotted a fee that looks wrong? Email [email protected].