How we calculate payouts
One formula, applied honestly per marketplace. No black boxes.
The core formula
| Gross | = item sale price + shipping charged to buyer |
| Total fees | = listing fee + commission + payment processing + per-order fee + any optional fees you toggled |
| Net payout | = gross − total fees |
| Profit | = net payout − your item cost (COGS) − your actual shipping cost |
| Effective fee % | = total fees ÷ gross × 100 |
Assumptions we make (and why)
| Assumption | Rationale |
|---|---|
| US sellers, USD, pre-tax | Fee schedules differ by country and sales tax is buyer-paid and remitted by the marketplace; mixing tax into fee math would misstate payouts. |
| One listing = one sale | Listing fees are charged per listing; we amortize one listing fee per calculated sale. If you renew listings repeatedly, your real cost is higher. |
| Grailed: no Grailed Label | Without a Grailed Label, buyer-paid shipping counts toward the commission tier (worst case). Using Grailed Labels lowers the commission base to the item price only. |
| eBay: "most categories" rate | We use 13.6% which covers most categories. Books/Movies/Music (15.3%), sneakers >$150 (8%) and a few others differ — check eBay's page for your category. |
| Poshmark: buyer pays shipping | The buyer pays Poshmark for a prepaid label, so your shipping cost is typically $0. We still let you enter your own shipping cost if you offer discounts or ship differently. |
| Poshmark commission base = item price | The $2.95/20% applies to the item price, not shipping, because shipping is a separate buyer-Poshmark transaction. |
| Vinted seller pays nothing | Vinted's only mandatory fee is buyer-side. Optional Item Bumps are off by default and shown as an approximation (prices vary per item). |
What we deliberately leave out
- Sales tax — collected from buyers and remitted by marketplaces; it never lands in your payout.
- Withdrawal / cash-out fees — e.g. Mercari Instant Pay is $3 per cash-out; direct deposit is free. These are banking choices, not sale fees.
- Currency conversion — v1 is USD-only. EUR support is planned.
- Shipping label rates — you enter your actual shipping cost, which is more accurate than any table.
- Subscription plans — eBay Shops, Etsy Plus etc. change fee economics only for high-volume sellers and are out of scope for a per-sale calculator.
Rounding
We compute on full precision and round to the cent only for display. Marketplaces round differently at the line level, so expect ±$0.01–0.02 differences versus your payout statement. The math is tested against worked examples — see the test suite.
Questions or a fee that looks wrong? The fee data lives in fees/*.json — every entry carries its official source URL.