Every other calculator shows you a number. TrueMargin shows you the number Amazon actually leaves you — after the referral fee, the FBA fee, the 1.5% fuel surcharge and the peak-period rate. Eight European marketplaces. VAT, inbound freight, storage, ad spend and return rate included. Nothing leaves your browser.
We read the one-star reviews of the two most installed Amazon fee calculators — 100,000 and 70,000 users, rated 3.9 and 3.5 — and counted what people complained about. TrueMargin is a direct answer to those five complaints.
Referral percentages that don't match Amazon, including the tiered categories. We parse Amazon's published schedule — all 52 categories, tiered rules included.
Sellers outside the US were left out. TrueMargin covers UK, DE, FR, IT, ES, NL, SE and PL from one official rate card.
No account, no email, no trial. Open a product page and the panel is already there.
The 1.5% fuel and logistics surcharge applies across European FBA since 17 April 2026, and peak-period rates run 15 Oct – 14 Jan. Both are calculated by default.
No dimensions entered? We pick the most expensive size tier that still fits your weight and tell you so. The profit you see is never flattering at your expense.
The lowest price you can charge without losing money — the number that decides whether a product is worth ordering at all.
What sellers reported about existing tools, and what TrueMargin does instead.
| What sellers complained about | Typical existing tool | TrueMargin |
|---|---|---|
| Fee percentages that don't match Amazon | Frequent complaint | Official schedule, versioned and sourced |
| Country coverage | US / EU only | 8 European marketplaces |
| Account or signup required | Signup wall | Nothing to sign up for |
| Fee data with no date on it | Rarely dated | Version shown inside the panel |
| Fuel surcharge and peak rates | Usually missing | Included by default |
| Optimistic profit when data is missing | Silent guess | Conservative tier + warning |
Every number in the extension comes from Amazon's own public documents. Nothing is estimated, and nothing is copied from a competitor.
Fees are extracted from the official PDFs, converted into a structured file, spot-checked against the source, and shipped inside the extension — not fetched from a server.
Fee history is kept in the open — so you can check that the tool is current instead of taking our word for it.
The calculator itself is free forever. Pro adds the bulk workflow sellers asked for in reviews — it is not built yet, and we won't pretend it is.
Amazon's own public documents: the FBA Rate Card for Europe (effective 1 July 2026) and the published UK referral fee schedule. Both links are shown in the extension, together with the data version.
No. The calculation runs in your browser. There is no analytics, no account, and no product or cost data is sent anywhere.
Amazon assigns the tier from the exact dimensions and weight on your listing. If you don't enter dimensions, TrueMargin deliberately uses the most expensive fitting tier, so the margin shown is never overstated.
Not yet. The current release covers the eight European marketplaces that share the official rate card. US coverage is next — we won't claim it before the data exists.