Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Profit per sale
$22.24
Net margin
44.49%
Total fees
$9.25
Platform take rate
31.5%
Break-even price
$22.90
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter sale price ($).
- 2Enter platform fee (%).
- 3Enter payment processing (%).
- 4Enter flat transaction fee ($).
- 5Enter shipping cost you absorb ($).
- 6Enter product cost ($).
- 7Read your profit per sale on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Between referral fees, payment processing, and shipping, marketplaces routinely take 20–35% of the sale price. Enter your own percentages to see the true net on any platform.
Worked example
Using the values the calculator loads with:
Inputs
- Sale price: 49.99 $
- Platform fee: 15 %
- Payment processing: 2.9 %
- Flat transaction fee: 0.3 $
- Shipping cost you absorb: 6.5 $
- Product cost: 12 $
Results
- Profit per sale: $22.24
- Net margin: 44.49%
- Total fees: $9.25
- Platform take rate: 31.5%
- Break-even price: $22.90
What each field means
Inputs
- Sale price ($)
- The sale price used in the calculation, measured in $. Starts at 49.99 $ so you have a working example on load.
- Platform fee (%)
- The platform fee used in the calculation, measured in %. Starts at 15 % so you have a working example on load. Accepted range: 0–50 %.
- Payment processing (%)
- The payment processing used in the calculation, measured in %. Starts at 2.9 % so you have a working example on load. Accepted range: 0–10 %.
- Flat transaction fee ($)
- The flat transaction fee used in the calculation, measured in $. Starts at 0.3 $ so you have a working example on load.
- Shipping cost you absorb ($)
- The shipping cost you absorb used in the calculation, measured in $. Starts at 6.5 $ so you have a working example on load.
- Product cost ($)
- The product cost used in the calculation, measured in $. Starts at 12 $ so you have a working example on load.
Results
- Profit per sale
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Net margin
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total fees
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Platform take rate
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Break-even price
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the marketplace fee calculator work?
Between referral fees, payment processing, and shipping, marketplaces routinely take 20–35% of the sale price. Enter your own percentages to see the true net on any platform. The underlying maths is: Net = Price − Platform fee − Payment fee − Shipping − Product cost.
What do I need to enter?
6 values: sale price, platform fee, payment processing, flat transaction fee, shipping cost you absorb, and product cost. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the profit per sale result mean?
It is returned as a money amount in US dollars and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Marketplace Fee Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/ecommerce-fees
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/ecommerce-fees" target="_blank" rel="noopener">Marketplace Fee Calculator — RevenueLab</a> (2026).</p>
Source: [Marketplace Fee Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/ecommerce-fees) (2026).