Four working calculators for the numbers Seller Central makes harder than they should be. No email gate, nothing stored, and the maths runs entirely in your browser. Fee tables updated for the 2026 rate card.
Net profit per unit after referral fees, FBA, storage, returns and advertising — plus the break-even ACoS your campaigns need to stay under.
Open the calculator CALCULATOR2026 rates. Works out your size tier, billable weight, fulfilment fee, the 3.5% fuel surcharge and referral fee per unit.
Open the calculator CALCULATORMonthly storage by size tier and season, with the aged-inventory surcharge that begins at 181 days and escalates past a year.
Open the calculator CALCULATORBillable weight, cubic feet and length plus girth. Shows whether dimensional or actual weight is driving your fulfilment fee.
Open the calculatorMost calculators tell you what a fee is. These tell you what it does to your margin.
The profit calculator applies referral fees to the selling price the way Amazon does, charges returns at unit cost plus fulfilment, and applies advertising only to the ad-attributed share of orders rather than to every order.
Amazon’s referral percentages, fulfilment fees and storage rates change, and vary by category, size tier and marketplace. For an exact figure, confirm against your own Seller Central fee preview.
These handle a single unit. The free audit rebuilds your whole catalogue into net profit per ASIN, which is usually where the loss-making products turn up.
Not ready to hand over access? Send one question about your account instead — ask without booking anything. Or read the numbers first on client results.