Know Your True Cross-Border Profit.
Most calculators multiply your landed cost by a tax rate and call it a day. Duty in the United States is assessed on the goods, not on the freight — get that wrong and you overstate your cost by a fifth. This one gets the basis right, and shows you where every number came from.
Amazon and CBP fees carry the official page they came from and the date we last checked it. Your own inputs and our estimates are labelled too, so you always know which is which — including the duty rate, which you supply because we do not look up HTS codes yet.
Leave out the returns settings and the returns fee is zero — most calculators just show you a healthy-looking profit. This one lists every cost block it skipped, and why.
Freight, advertising and return rates are unknowable in advance, so they come as ranges across a conservative, base and optimistic case. A single confident number would be a lie.
Two calculators so far, covering Amazon US. Bulky and extra-large fulfilment fees have a known discrepancy against Amazon’s own calculator and say so on the results page. Guides, more markets and VAT are not built yet — and will not be claimed until they are.