Marketplace Fee Calculator
See the payout before you list: a 125 sale with a 12.5% marketplace fee and a 0.3 fixed fee costs 15.93 in fees and leaves a net payout of 109.07. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Sale price
- 125
- Percentage fee
- 12.5
- Fixed fee
- 0.3
- Percentage fee amount
- 15.63
- Total fees
- 15.93
- Net payout
- 109.07
A marketplace sale is not the same as the amount that reaches the seller. This calculator takes the gross sale price, the marketplace percentage fee, and the fixed fee charged for each transaction, then returns the percentage charge, combined fees, and final net payout. It is useful for checking listing economics, comparing platforms, and setting prices before a product goes live. If the entered fees would be greater than the sale price, the calculation stops with a clear error instead of presenting a misleading negative payout.
Enter the marketplace fee structure correctly
Start with the gross sale price paid for the item before marketplace deductions. Enter the percentage fee as a normal percentage: for example, use 12.5 for a fee of twelve and a half percent, not 0.125. Then enter the fixed fee that the platform charges once for the transaction.
All three amounts must be nonnegative, and the sale price must be greater than zero. The calculator is currency-neutral, so the sale price and fixed fee simply need to use the same currency. If the listing is priced in dollars, enter the fixed fee in dollars; if it is priced in euros, use euros throughout.
Taxes, shipping labels, advertising charges, payment reserves, refunds, and currency conversion costs are not inferred because marketplaces apply those items differently. Include only the percentage and fixed transaction fees you actually want to model. This narrow contract makes the result easy to audit against a marketplace’s published seller fee schedule.
Understand the fee calculation and rounding
The calculator multiplies the sale price by the percentage fee divided by one hundred. It rounds that percentage charge to two decimal places, adds the fixed transaction fee, and rounds the combined fees to two decimal places. The net payout is the sale price minus the combined fees, also rounded to two decimals.
This sequence reflects the way a typical currency transaction is presented and makes every intermediate value visible. When combined fees are exactly equal to the sale price, the net payout is zero and the calculation remains valid.
Use net payout to make better pricing decisions
Run the calculation before publishing a listing, then compare the net payout with the item cost, packaging, shipping contribution, labor, and desired profit. The payout is not profit by itself; it is the amount remaining after only the two marketplace charges supplied to this calculator. For platform comparisons, keep the sale price constant and calculate each marketplace’s percentage and fixed fee separately.
For price testing, change the sale price while keeping a platform’s fee schedule constant, then observe how the fixed fee has a larger relative effect on inexpensive items. Because the algorithm uses no network service, stored state, random values, or current date, the same valid inputs always produce the same result.
What you can do with it
Set a profitable listing price
Estimate the amount left after core marketplace charges before comparing it with product cost and target margin.
Compare selling platforms
Apply each platform’s percentage and fixed fee to the same sale price and compare the resulting seller payouts.
Audit a transaction estimate
Reproduce the basic fee breakdown shown in a marketplace calculator or seller documentation with visible intermediate values.
FAQ
Does the result represent my profit?
No. Net payout is the sale price after the entered marketplace fees only. Subtract inventory, shipping, taxes, advertising, labor, and other costs separately to calculate profit.
How is the marketplace net payout calculated?
The sale price is multiplied by the percentage fee over one hundred, rounded to two decimals, and the fixed fee is added. For a 125 sale at 12.5% plus 0.3, that is 15.63 plus 0.3, or 15.93, leaving 109.07.
Do I enter 12.5 or 0.125 for a 12.5% fee?
Enter 12.5. The percentage fee is written as a normal percentage, so 0.125 would be read as a tiny fraction of one percent and the fees would come out far too low.
What if the fees are higher than the sale price?
The calculation stops with a clear message instead of showing a negative payout that no marketplace would deposit. If the fees exactly equal the sale price, the payout is zero and the result is still valid.
Why does the fixed fee matter more on cheap items?
Because it stays the same whatever the price, so it takes a bigger share of a small sale. Keep one fee schedule and change only the sale price to see how the payout shifts on low-priced listings.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/ecom/marketplace-fee-net-calc \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"sale_price":125,"percentage_fee":12.5,"fixed_fee":0.3}'const res = await fetch("https://api.kit.forhosting.com/ecom/marketplace-fee-net-calc", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"sale_price": 125,
"percentage_fee": 12.5,
"fixed_fee": 0.3
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/ecom/marketplace-fee-net-calc",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"sale_price": 125,
"percentage_fee": 12.5,
"fixed_fee": 0.3
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/ecom/marketplace-fee-net-calc", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"sale_price":125,"percentage_fee":12.5,"fixed_fee":0.3}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"sale_price":125,"percentage_fee":12.5,"fixed_fee":0.3}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/ecom/marketplace-fee-net-calc", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"sale_price": 125,
"percentage_fee": 12.5,
"fixed_fee": 0.3
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "ecom.marketplace_fee_net_calc",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
Understand the fee calculation and rounding
The response repeats the normalized inputs alongside percentage_fee_amount, total_fees, and net_payout, so you can trace the result without reconstructing hidden arithmetic. When fees exceed the sale price, the request returns an input error. That safeguard prevents a negative payout from being mistaken for an amount the marketplace will deposit and highlights listings whose basic fee structure is economically impossible.
Use net payout to make better pricing decisions
Automated sellers can call the API for each proposed price or product and store the returned breakdown beside their pricing decision. Each request costs $0.002.
Technical questions
What does the calculator cost to use through the API?
Each API request costs $0.002.
How should I enter a 15 percent marketplace fee?
Enter 15 as the percentage_fee. Do not enter 0.15.
Can I use currencies other than US dollars?
Yes. The calculation is currency-neutral as long as sale_price and fixed_fee use the same currency.
What happens when the fees are greater than the sale price?
The request returns an invalid_input error stating that total marketplace fees exceed the sale price.