Trust & transparency
Methodology & sources
A fee calculator is only useful if its numbers are right. Here is exactly where our rates come from, how they're maintained, and what changed when.
The rules behind every result
All six calculators run on a single versioned fee-rule set — currently v2026.07.0, last verified July 13, 2026. Each rate in that set records the official page it came from and the date we last checked it. When a marketplace changes a fee, we update the rule set once, bump the version, and note it in the change log below — every calculator and every rate table on this site updates together, because they all read from the same data.
- Official sources only. Rates are read from marketplace fee pages and policy documents — never from other calculators or blog posts.
- Regression tested. Every rule is pinned by automated tests with hand-worked examples (tier boundaries, fee thresholds, tax bases), so an update that breaks a calculation fails loudly before it ships.
- Estimates, clearly labeled. Marketplaces apply account-specific promotions, credits, and categorization we can't see. Results are estimates; your seller dashboard is the source of truth for your account.
What we model (and what we don't)
We model the published per-sale fee mechanics: percentage fees and their exact bases (including whether sales tax and shipping are inside the base — the most common error in fee calculators), fixed per-order fees and their thresholds, category exceptions and tier structures, store-subscriber discounts, performance surcharges, promoted-listing ad rates, and international fees. We do not model one-off promotions eBay or Etsy may run for your account, negotiated enterprise rates, currency conversion, or taxes on fees where they apply. Subscription costs (like eBay Store fees) are treated as fixed monthly overhead, not per-sale fees.
Change log
| Date | Version | Changes |
|---|---|---|
| 2026-07-13 | 2026.07.0 |
|
For more context on major changes, read our updates on the July 2026 eBay performance surcharges and the July 2026 USPS dimensional-weight rule.
Sources on file
Every rate in v2026.07.0 traces to one of these official pages, each last checked 2026-07-13:
- eBay — Selling fees (final value fees, per-order fee, surcharges)
- eBay — Store selling fees (subscriber rates & subscriptions)
- eBay — Seller standards policy (Top Rated discount)
- eBay — Promoted Listings general campaigns
- eBay — July 1, 2026 selling-fee changes announcement
- eBay — Fee credits (refund & cancellation rules)
- Etsy — Fees & payments policy
- Etsy — What are the fees and taxes for selling on Etsy?
- Etsy — Payment processing fees
- Etsy — How Offsite Ads work
- Whatnot — Seller fees
- Whatnot — Reduced commission on Coins & Money
- Whatnot — High-value orders commission promotion
- USPS — July 12, 2026 DMM revision (dimensional weight divisor and rounding)
- UPS — Shipping dimensions & weight
- FedEx — What is dimensional weight?
Corrections
Spotted a rate that doesn't match what your seller account shows? Email info@sellafterfees.com with a screenshot — verified corrections ship within days and are credited in the change log.