Methodology

How we source fee data

The baseline platform fee data behind FeeCalculate's calculators — Etsy, eBay, Amazon FBA, Poshmark, and Shopify — is compiled from public sources: platform help-center pages, seller forums, and third-party seller-tool commentary, cross-checked across multiple independent sources rather than taken from any single one. Where we can verify a rate directly against a platform's own official documentation, we do, and we treat that as our highest-confidence tier. For example, Etsy's Regulatory Operating Fee figures used on this site were fetched and confirmed directly against Etsy's own official help center documentation for each country we display a rate for.

Not every fee is publicly documented, and we'd rather say so than guess. Amazon restructured its FBA fulfillment fees in 2026 into a size tier × weight × selling-price system, but the exact dollar table for that system is only visible inside a logged-in Seller Central account — it isn't on any public Amazon page. Rather than publish a number pulled from an unverified third-party blog, the Amazon FBA calculator explains this directly and asks you to enter your own exact fulfillment fee from Seller Central's Fee Preview report instead.

What "Fees last verified" means

Every calculator shows a "Fees last verified" date near the top of the page. That's the date the underlying fee figures for that specific calculator were last checked — not a guarantee that the platform's pricing hasn't changed since. We don't have a fixed weekly or monthly review schedule to promise you here: fee data is reviewed periodically, and re-checked whenever we become aware a platform has announced a fee change, a reader reports something looks off, or we're actively working on that calculator for another reason. If a pricing decision depends on being exactly right, treat the date as a "last checked" timestamp and confirm against the platform's own current fee page too.

Estimated vs. verified numbers

Some numbers on FeeCalculate are explicitly marked as estimates rather than confirmed figures, because we'd rather flag uncertainty than hide it. A few examples you'll see across the site: the Amazon FBA calculator labels a result "Estimated — select a category for accuracy" until you've chosen your product's actual category, since Amazon's referral fee varies significantly by category; the Marketplace Fee Matrix shows a currency disclaimer noting that currency conversions use approximate rates for illustration, not live market rates, while the underlying fee percentages themselves are unaffected; and several calculators note when a default value is a typical example rather than your specific number. When a calculator can't verify a figure specific to your exact situation, it tells you what it's estimating and why, instead of presenting a guess as a fact.

How to report an error

If you find a fee that looks outdated, wrong, or missing entirely, tell us via our Contact page. Include which calculator, what number looks wrong, and — if you have it — a link to the platform's current official fee page. We read every message and use them to prioritize what gets re-verified next.

About this site

FeeCalculate is a free, ad-supported website built and maintained by the FeeCalculate team. We don't publish individual author bylines or credentials on calculator pages, because we'd rather be straightforward about our actual sourcing process — described above — than attach a name or credential to it that doesn't add real verification value. See About FeeCalculate for more on what the site is and who it's for, and our Privacy Policy for how we handle data.