Contribution Margin Calculator
Calculate contribution margin from price and variable cost per unit — the figure the Break-Even ROAS and Break-Even CPA calculators need.
Formula
Contribution Margin = Price − Variable Cost per Unit
Contribution margin is not the same as gross margin. Gross margin usually subtracts only cost of goods sold. Contribution margin subtracts every non-advertising cost that scales with the sale — if you leave out payment processing, shipping, or marketplace fees, the result will be too high.
Worked Example
A product sells for $100. Cost of goods is $40, payment processing is $3, and fulfillment is $7 — a total variable cost of $50. Contribution margin = $100 − $50 = $50 (50%).
Use this percentage directly in the Break-Even ROAS Calculator or the Break-Even CPA Calculator.