Enter your buy price, expected sale price, and costs. See exact net profit, margin, and ROI. Works for all platforms.
Before you buy that thrift store find, enter what you'll pay and what you expect to sell it for. The calculator subtracts every cost — platform fees, shipping, supplies, repairs — to show your real net profit.
Margin = net profit ÷ sale price × 100. This tells you what percentage of the sale you keep. Most resellers target 40–50%.
ROI (return on investment) = net profit ÷ your total cost × 100. This tells you how much you earned relative to what you spent. A $10 buy that nets $20 profit is 200% ROI.
| Platform | Fee Structure | Fee Applies To |
|---|---|---|
| eBay | ~13.25% final value fee | Total sale (item + shipping) |
| Poshmark | 20% (or $2.95 under $15) | Item price only |
| Mercari | 10% selling fee | Item price + buyer shipping |
| Depop | ~3.3% + 2.9%+$0.30 processing | Total sale |
| Etsy | 6.5% + 3%+$0.25 payment | Item + shipping |
| FB Marketplace | 0% local; 5% shipped | Varies |
Most experienced resellers target 40–50% margin after all fees, plus a minimum $10–$15 net profit per item. The "thirds rule" is a quick heuristic: buy for 1/3 of expected sale price, and the remaining thirds cover fees and profit.
Yes, for sales $15 and above, Poshmark takes a flat 20% commission. For sales under $15, the fee is a flat $2.95. This means a $14 sale costs 21% in fees, but a $15.01 sale only costs 20%. Pricing items between $13–$15 is usually a mistake.
Margin = profit ÷ sale price (what % of revenue you keep). ROI = profit ÷ your cost (how much you earned on your investment). A $5 buy sold for $40 with $12 in fees gives: margin = ($40-$5-$12)/$40 = 57.5%, ROI = $23/$5 = 460%. Resellers use ROI for sourcing decisions and margin for pricing.
It depends on the platform. eBay charges its final value fee on the total (item + buyer shipping). Poshmark charges 20% on the item price only. Mercari charges on price + shipping. Use the "Fee applies to" dropdown to match your platform.
This calculator shows per-item profit on a successful sale. To account for unsold inventory, track your sell-through rate. If you buy 10 items at $8 each ($80 total) and sell 7 with an average $15 profit, your true ROI includes the 3 unsold items' cost ($24) spread across the 7 sales.
Our AI Pricing Copilot shows your exact profit on eBay, Poshmark, Mercari, Depop & Etsy at once — so you list at the right price everywhere.
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