How to Calculate Profit After Marketplace Fees (2026)

By the Profitvana Editorial Team · Updated May 2026

The price a buyer pays is not what you keep. Between platform fees, payment processing, and your own costs, your real profit can be a fraction of the headline sale price. Here is the formula that turns a sale into honest profit — and the trap most sellers fall into.

Why "sale price" is not your profit

Every marketplace sale has three layers. Layer one is the amount the buyer pays you (item price plus any shipping). Layer two is what the platform takes — commission, transaction fees, payment processing, sometimes ad fees. Layer three is what the item cost you to make or buy, plus your shipping cost.

Profit is what survives all three. Most sellers anchor on the sale price and only realize at month-end that they earned far less than they thought, because they never priced in layers two and three.

The formula

Net profit = (sale price + shipping charged) − total platform fees − (item cost + your shipping cost). Profit margin = net profit ÷ (sale price + shipping charged) × 100.

Use the gross (item plus the shipping you charge the buyer) as the base because that is what fees are usually applied to. Then subtract every fee line — including the per-order flat fee a lot of platforms add on top of their percentage — and finally subtract your own costs.

Worked example on a $100 sale

Say you sell an item for $100 with $10 buyer-paid shipping on a platform that charges 13.6% plus a $0.40 per-order fee. Your item cost you $40 and the shipping label cost you $8.

Gross revenue: $110. Platform fees: 13.6% × $110 + $0.40 = $15.36. Your costs: $40 + $8 = $48. Net profit = $110 − $15.36 − $48 = $46.64. That is a 42.4% margin on gross — a healthy number, but very different from "$100 minus $48 = $52" if you ignored fees.

Hidden costs most sellers miss

International payment fees (often +1.5%), refunds and chargebacks, promoted-listing ad spend, monthly subscriptions spread per sale, and the cost of returns. Each one shaves a little more off your margin.

Track them by category. Even a 1% slip across a month of sales is real money. Tools like the calculators on this site let you plug in your numbers per platform so you see exactly what is left.

When to recalculate

Whenever a fee changes (most platforms updated rates in 2025–2026), when you change category or store tier, when you turn promoted listings on or off, or when shipping costs move. A quick recalculation can stop you pricing below your break-even point.