Mercari's fees, and the one people get wrong
Mercari's fee structure is refreshingly simple once you know which fee belongs to whom. As a seller you pay one thing: a 10% selling fee calculated on the item price plus whatever shipping the buyer paid. There is no separate payment-processing charge stacked on top, which is what makes it cheaper per sale than most marketplaces.
The part that trips people up is the 3.6% Buyer Protection fee. It is charged to the buyer at checkout, not to you, and it does not come out of your payout. Plenty of fee calculators and forum posts subtract it from the seller's side anyway, which makes every deal look worse than it is. This calculator keeps the two strictly separate: your fees are your 10%, and the buyer's fee is shown underneath purely as context, because it does change what your listing costs someone at checkout.
Fee table — verified 2026-07-30
| Fee | Who pays | Amount |
|---|---|---|
| Selling fee | Seller | 10% of item + buyer-paid shipping |
| Payment processing | Seller | None |
| Buyer Protection fee | Buyer | 3.6% of item + buyer-paid shipping |
Current schedule effective 2025-01-06. Verified 2026-07-30 against Mercari's own Fees on Mercari help page. Mercari has changed this structure more than once, so much of the advice online describes an older model — check the date on any figure you are relying on, including this one.
How this calculator works
It builds the fee base first: sale total = item price + shipping you
charged the buyer. It takes 10% of that as Mercari's selling
fee, and nothing else, because sellers are not charged processing. What is
left is your payout. Then it subtracts your side: what you paid for the item,
your shipping label, and any other costs you entered.
Profit is the payout minus those costs. Margin expresses that profit as a share of the sale — how much of what the buyer paid you kept. ROI expresses it against what the sale cost you, which is the number that matters most if you source cheaply: a $6 item that clears $26.50 is a 58.9% margin but a 442% return on cost. Money is rounded to the cent, and the same function that runs in your browser is the one the unit tests assert against the worked examples below.