WHERE OUR NUMBERS COME FROM
Trust is the whole product. Here is every official source behind CLAWBACK, the date we last verified it, and the exact method we use to turn policy text into your loss figure.
Official sources (verified August 2026)
| Platform | What we source | Official page |
|---|---|---|
| eBay | Final value fee %, per-order fee tiers, fee-credit-by-reason, return-shipping rules | fee credits · selling fees · return shipping |
| Poshmark | 20% / $2.95 commission, prepaid return labels, Seel Worry-Free Returns | Poshmark support |
| Mercari | 10% selling fee (2025), 50-lb return-label rule, 3.6% buyer protection | refunds & returns · help center |
| Depop | $0 US selling fee, 3.3% + $0.45 processing, all-fees-refunded-on-refund | Depop help |
| Whatnot | 8% / 4% commission, 2.9% + $0.30 processing on gross order value, $1,500 high-value cap, per-checkout fee, carrier weight clawbacks | seller fees · seller protection · $1,500 cap promo |
| Vinted | $0 seller fees, $0.70 + 5% buyer protection (buyer-paid), prepaid shipping labels | price list · shipping · refund policy |
Our method, in one line
Loss = fees the platform keeps + return shipping you paid + the drop in the item's value. For eBay, which fees are kept depends on the return reason, so we ask "what happened?" and apply the matching fee-credit rule from eBay's own policy. For the others, approved returns reverse fees, so the loss is dominated by value drop and (for Mercari heavy items) shipping. For Whatnot, the calculator also exposes the "bite ratio" — the real effective fee rate when you include processing on gross order value and carrier clawbacks.
How we stay current
- Re-verification every quarter (Jan / Apr / Jul / Oct), plus whenever a platform emails a policy change.
- The footer and this page always show the last-verified date — if it's stale, call us out.
- Corrections from sellers are treated as bug reports and checked against the official page before we change a number.