About Marginely

Marginely is an independent seller-tools site. We publish free calculators that show what a marketplace sale actually costs — referral and fulfilment fees, currency conversion, reimbursements, inbound placement and shipping surcharges — so the margin is visible before you price a product or send inventory.

What we publish

Every tool is free, needs no signup, and runs entirely in your browser:

• Amazon selling fee calculator — referral fee by category plus the 2026 FBA fulfilment fee, profit and ROI.
• Amazon referral fees by category — the full table, including tiered rates.
• FBA reimbursement calculator and inbound placement fee calculator.
• Amazon currency converter (ACCS) fee calculator and cash flow calculator.
• Walmart and TikTok Shop fee calculators, and the FedEx/UPS surcharge calculator.
• Checklists for FBA shipments, hazmat review and category ungating.

The calculators can also be embedded on your own site free of charge.

Where the numbers come from

Rates and rules are taken from the marketplace's own published schedules — Amazon's Seller Central referral fee schedule and FBA fulfilment fee tables, and the equivalent published pricing for the other marketplaces we cover. Each tool page lists the official sources it was built from and carries the date it was last reviewed. We re-check a page after each announced fee change rather than on a fixed calendar.

Independence

Marginely is not affiliated with, endorsed by, or compensated by Amazon or any other marketplace. No payment is accepted to alter a rate or a recommendation. The site is supported by advertising and, on some pages, by affiliate links that are disclosed beside the link; commissions never change the figures shown or the order of a comparison.

Found a rate that no longer matches your Seller Central account? Tell us — accuracy reports are handled first.

Results are estimates from published schedules, not financial, tax or legal advice.