Marketplace Fee Price Builder is a free online tool that builds a selling price that covers listing, transaction and payment fees at rates you enter, and shows your net proceeds. It runs entirely in your browser, so you do not need to install anything, create an account, or share your business figures with anyone. You open the page, type in your own numbers, and get a clear result in seconds. Small sellers often do this pricing math by hand or in a rough spreadsheet, and this tool replaces that slow work with a simple form you can reuse for every product and every order.
It is made for sellers on marketplaces who want a price that still leaves a profit after every fee. Clear pricing protects both sides of a sale. A buyer who sees a fair price is more likely to buy and less likely to complain later. A seller who knows the true cost behind a price knows which products make money and which ones only look busy. This tool keeps those facts visible, written down, and easy to check before you commit to a price.
You start by entering your product cost, the profit you want, and each fee rate as a percent. Use real figures from your own business where you can, not round guesses. If you are unsure about a figure, use your best careful estimate and then test a slightly worse figure as well. That second test shows how sensitive your result is. A price that only works when every figure is perfect is a fragile price, and it is better to find that out here than after you have promised it to buyers.
Take this worked example: a product that costs $20, a profit target of $10, and fees of 5%, 3% and 2%. The tool shows a selling price near $33.33, total fees near $3.33, and net proceeds of $30.00. Notice how the answer is not just one number. It breaks the result into its parts, so you can see where each figure comes from. That breakdown is the useful part, because it tells you which input to change if the final result is too high, too low, or simply unfair for your business or your buyer.
The result matters because fees are charged on the selling price, not on your cost, so a price that only adds fees to cost will always fall short. Many small sellers look only at the headline price and forget what sits behind it. A price can look complete and still miss a fee, a stall share, a waste allowance, or a shipping cost. Reading the full result, not just the headline, is what turns a figure into a decision rather than a hope, and turns a guess into a price you can defend.
A common mistake is adding all the fee percents to your cost and calling that the price, which leaves you short once fees are taken from the higher price. It is easy to make because the mistake feels reasonable at the time. A quick price feels faster than a full cost sheet, and an equal split feels fair without checking the numbers. Both can be true and still cause trouble if the details underneath do not support them. The tool helps you catch that problem before anyone pays, while it is still cheap to fix.
Test a higher fee rate than you expect, because marketplaces change rates and payment fees vary by method. This is a practical habit, not a theory. Run the version you want, then run a second version with a tougher input, such as higher costs, fewer sales, or a higher fee. Compare the two results and ask yourself which one you could live with if the next few weeks are slow. The best price is often not the lowest one. It is the price that still works when conditions get harder.
There are limits to what a simple tool can do. it uses the rates you enter and cannot know about refunds, discounts, taxes or shipping costs you did not include. It cannot predict how buyers will react, how a market day will go, or what a tax authority will decide in your case. Those questions need real records, written terms, and professional advice where the stakes are high. What the tool can do is make sure the price and the arithmetic behind your plan are sound, so that if the price is agreed, the numbers in it are correct.
The figures here are estimates for planning only, not professional financial, legal, or tax advice. Your real prices, costs, fees, and sales terms may differ, and you should check important decisions with your own records or a qualified adviser where needed. Used that way, this free tool is a practical helper for everyday small business pricing. Enter honest figures, read the full result, test a few versions, and choose the price that is fair, clear, and easy to explain to everyone involved.