Marketplace fee & profit calculator for Amazon, eBay, Etsy and card processors. Free, no signup, and there's a JSON API underneath.
One row per SKU: sku,price,cost — paste straight from a spreadsheet export. Runs in your browser; nothing is uploaded.
The same fee math over HTTP, so you can price inside your own tooling: /v1/fees/amazon, /v1/fees/ebay, /v1/fees/etsy, /v1/fees/processor, plus /v1/price/target which solves for the price that hits a target margin. JSON in, JSON out, CORS open.
It is in private beta while I keep the fee schedules current — email for access and tell me which marketplaces you need.
The calculator above is free and stays free. If you have hundreds or thousands of SKUs, send the CSV and get back every SKU’s fees, net profit, margin and break-even price, with the money-losers flagged and the price each one needs to hit your target margin.
Up to 5,000 SKUs · delivered within 24 hours · refunded if it’s not useful.
Pay $9 → what you get & how to send your file
Prefer crypto? USDC on Base: 0xFFCf58d4b2a8b2B90907DE5BAE4965D80Ab7A1A1
Rate tables and worked examples, updated for 2026:
Got more than one SKU? Paste your whole catalog as CSV and get every SKU's fees, net profit, margin and break-even price in one table — free, no signup, and it runs entirely in your browser so nothing is uploaded.
Exact fee breakdowns for the prices sellers ask about most.