BACKLANE / TOOLS FOR SELLERS
Margin calculator
What is left from your sale?
Work through a sale with your variable costs. Calculate the price floor, target-margin price and discount headroom for your offers.
No sign-up · Calculated in your browser
01 / INPUT
Your inputs
English number format, for example 1,000.50. All monetary amounts are in EUR, excluding VAT.
In percentage mode your rate must be based on net selling price. Convert other charging bases yourself; no marketplace fee schedules are fetched.
Revenue per unit sold, excluding VAT. EUR
Purchase cost for this unit. EUR
Amount per sale from your calculation or statement. EUR
Your variable costs per unit. EUR
Advertising cost allocated to this unit. EUR
For example, your own estimate of return costs per sale. EUR
Share of net revenue after the variable costs entered. Optional, 0 to less than 100%.
Fictional example loaded. Replace these figures with your own inputs.
02 / OUTPUT
Your result
Enter your figures and calculate the result.
- Contribution
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- Margin on net revenue
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- Total variable costs
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- Break-even ROAS
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Price thresholds for your offers
- Variable-cost price floor
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- Price at target margin
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- Discount headroom to target price
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Price thresholds are rounded up to whole cents; discount headroom is rounded down to two decimal places. Product, shipping, ad and other costs remain fixed per unit; only the percentage selling fee changes with price. Fixed overheads and missing costs are excluded.
This is a contribution calculation, not a full profit calculation. Fixed costs, taxes and costs you have not entered are excluded. This tool does not provide current marketplace fee schedules. Enter the appropriate net costs for each channel; missing costs should not be treated as confirmed zeros.
This tool processes your inputs locally in your browser. It does not upload your figures or files, or save them permanently.
03 / METHOD
How the calculation works
Contribution = net revenue − included variable costs
Margin = contribution ÷ net revenue × 100. With fee rate g and target margin m expressed as decimals: price floor = other variable unit costs ÷ (1 − g); target price = other variable unit costs ÷ (1 − g − m). For positive unit costs the target denominator must be positive. With no other unit costs, a reachable target uses a minimum price of €0.01. In amount mode entered fees form part of constant unit costs. Discount headroom = max(0, (current price − rounded-up target price) ÷ current price × 100), rounded down to two decimal places. Other unit costs remain constant. Break-even ROAS uses contribution before advertising when positive.
An example to work through
Fictional example: €100 net revenue less €40 product cost, €15 fees, €5 shipping, €10 advertising and €5 other costs gives €25 contribution and a 25% margin. Contribution before advertising is €35 and break-even ROAS is about 2.86.
This is a contribution calculation, not a full profit calculation. Fixed costs, taxes and costs you have not entered are excluded. This tool does not provide current marketplace fee schedules. Enter the appropriate net costs for each channel; missing costs should not be treated as confirmed zeros.
CONTINUE WITH YOUR OWN MARKETPLACE DATA
Which offers fall below your price thresholds?
Compare available offer prices from connected marketplaces with your own price thresholds. Add purchase costs and internal costs when needed.
BACKLANE / STARTER PROMPT
Compare available current offer prices for my selected products across connected marketplaces with my own price thresholds. Ask me for the threshold per item and its VAT basis. Check product matching and show offers below my threshold. If a threshold still needs calculating, ask for missing purchase costs, fees and other variable costs. Flag missing data. Do not change prices.
Frequently asked questions
What is the difference between margin and markup?
This calculator expresses margin as a share of net revenue. Markup uses the cost basis instead. A €20 difference on €100 revenue is a 20% margin; the same €20 on an €80 purchase cost is a 25% markup.
Does Backlane provide every cost automatically?
Backlane can use available offer, order and other marketplace data. You need to add purchase costs, internal shipping costs or cost assumptions when connected systems do not supply them.