E-commerce Profit Calculator

What this tool does

A product listed at 99 looks healthy until platform commission, inbound cost, shipping, return losses and ad spend are taken out. Guessing the remainder tends to omit one of them. This calculator lists each cost as its own input and returns gross profit per unit, net profit, net margin and the break-even quantity, with preset fee rates for common marketplaces.

The arithmetic runs in a fixed order: subtract commission (price times rate), purchase cost, shipping, packaging and other unit costs from the selling price to get gross profit; then discount expected orders by the return rate and spread the advertising budget over expected volume to reach net profit. At a price of 99 with 5 percent commission, 45 purchase cost, 6 shipping, an 8 percent return rate and 8 of ad allocation per unit, the net figure is far below the naive 99 minus 45.

The result panel also reports break-even volume, which is fixed cost divided by net profit per unit. Changing any rate or cost recalculates every output in place without a page reload.

The order of operations is fixed and worth understanding before trusting the result. Commission is taken as a percentage of the selling price, then purchase cost, shipping, packaging and any other per-unit costs are subtracted to reach gross profit. Return rate then reduces the number of orders that actually generate revenue, and the advertising budget is divided by expected volume and charged against each surviving unit. Treating ad spend as a lump sum at the end, or ignoring returns, is what makes a back-of-the-envelope margin look much healthier than the settlement statement. Fixed costs, where entered, are divided by net profit per unit to give break-even volume; if that unit figure is zero or negative the tool says so rather than printing an infinite or negative quantity. Preset commission rates are typical ranges for common marketplaces, not contractual numbers, because campaign fees, category differences and negotiated rates all move the real deduction. Tax, shipping insurance, after-sale compensation and platform deposit adjustments are outside the model, so list them separately in your own sheet. Percentages are entered as plain numbers without a percent sign, and a stray symbol produces a validation message instead of a silent zero. Because return rate and sales volume are forecasts, the output is a planning figure; the seller dashboard settlement is the number that actually reaches the bank account.

Key features

• Preset platform rates: Common marketplace commission rates load with one click, or enter your own percentage.
• Return-rate adjustment: Expected orders are reduced by the return rate so returned orders are not counted as full revenue.
• Ad cost allocation: Advertising budget is spread over expected volume, keeping gross profit from overstating the real margin.
• Break-even volume: Fixed cost divided by net profit per unit gives the minimum number of sales to avoid a loss.
• Quick sensitivity checks: Change price or a fee rate and watch net margin move, which is useful before setting a promotion.
• Copy-ready output: The result block copies as aligned lines of price, rates and net profit for a report.

How to use it

1. Enter price and costs: Fill selling price, purchase cost, shipping, packaging and other per-unit costs.
2. Choose a fee rate: Pick a marketplace preset or type the commission percentage directly.
3. Add returns and ads: Enter expected return rate, ad budget and expected sales volume for the allocation.
4. Press Calculate: The panel returns gross profit, net profit, net margin and break-even volume.
5. Test a price change: Adjust price or a rate and recalculate to compare promotional scenarios.

Things to keep in mind

• Contract rates apply: Presets are typical ranges; actual commission and campaign fees come from your seller dashboard and contract.
• Tax and refunds excluded: Only the unit costs you enter are counted, so VAT, shipping insurance and after-sale payouts belong on a separate line.
• Percentages as numbers: Enter commission and return rates as plain numbers without a percent sign, which is rejected as invalid.
• Estimates are not settlement: Return rate and volume are forecasts; the platform statement is the source of truth.
• Local data only: Costs and prices are never uploaded and vanish on refresh, so keep your own copy of sensitive quotes.