How to use the Mercari seller profit calculator
Enter item sale price, shipping charged to buyer, item cost, seller shipping cost, fee assessment base, combined percentage fee (%), fixed fees, and other transaction costs. Choose the currency for your inputs and read the result as you change the values.
How it works and formula
Platform fees = fee base × percentage rate + fixed fees. Net profit = sale price + buyer shipping − item cost − seller shipping − platform fees − other costs.
Worked example
| Item sale price | 100 |
|---|---|
| Shipping charged to buyer | 5 |
| Item cost | 40 |
| Seller shipping cost | 5 |
| Fee assessment base | 105 |
| Combined percentage fee (%) | 10 |
| Fixed fees | 0.50 |
| Other transaction costs | 6 |
Result
Platform fees $11.00
Net profit $43.00
Choosing your inputs
Enter the sale price and any shipping paid by the buyer as separate amounts. Enter your inventory cost and what you paid to ship it. The fee base is the amount the platform charges its percentage on. Enter the seller-side fees and shipping charges actually deducted from your payout. Use the order breakdown to identify which costs belong to the seller.
How to interpret the result
In the worked example, $105 is subject to the percentage fee. Each additional percentage point reduces the profit by $1.05 when the base stays the same. If you offer free shipping, leave buyer shipping at zero and enter your postage expense as seller shipping.
Frequently asked questions
How should I enter other transaction costs?
Use the separate other transaction costs field for this expense and enter it only once. Set the fee base to the amount your seller statement actually uses.
What if two fees use different bases?
Calculate the separate charge from its own base and add that dollar amount under other costs or fixed fees. Count each deduction once.