Reseller Fee and Profit Calculator

Every platform takes its cut differently. eBay charges on the total including shipping, plus a per-order fee. Whatnot charges commission on the item but processing on everything. Poshmark takes 20% but the buyer pays the label. Depop has no selling fee, but charges processing. Doing that maths for every item, or working backwards to a price that makes $20, is where resellers lose money without noticing.

This skill uses a bundled script and an editable fee file in which every profile names its source and the date it was checked. Quote compares fees, payout, profit, margin and ROI at one price across platforms. Target finds the lowest whole-cent price that reaches your profit goal, or breakeven, on each platform. Batch works out profit for every row of an items CSV. The maths covers payment processing charged on shipping and tax, eBay's lower per-order fee on small orders, eBay Live's $100 commission cap, Poshmark's flat fee under $15, promoted-listing and boost rates, shipping charged and paid, supplies and item cost. The AI then explains which platform keeps the most and why.

Inside: SKILL.md, the calculator script (Node.js, no packages), the fee file (eBay, eBay Live, Whatnot, Poshmark, Depop, Etsy, Facebook local, in person, plus fill-in profiles for Mercari, Facebook shipped and TikTok Shop), fee notes, and hand-checked examples.

For resellers choosing where to list and what to charge.

Limitations: fees change and some depend on category, subscription or volume (checked October 2026). Profit is before income tax, and this isn't tax advice.