Contribution Margin Calculator
See how much each sale contributes toward covering your fixed costs and profit. Enter price and variable costs per unit to get contribution margin, the ratio, and your break-even unit volume.
Per-unit & fixed costs
COGS, fees, shipping and per-order ad cost.
Rent, salaries, software — costs that don't change with volume.
Results
- Contribution margin / unit
- $22.00
- Contribution margin ratio
- 44.0%
- Break-even volume
- 364 units
Price minus variable cost.
Units needed to cover fixed costs.
Calculations run live in your browser. Nothing is stored.
What this measures
Contribution margin is the money left from each sale after variable costs, available to cover fixed costs and then profit. It isolates the per-unit economics from overhead.
Once contribution margin covers all fixed costs, every additional unit's contribution drops straight to profit — which is why it's the basis for break-even analysis.
The formula
Contribution margin = Price − Variable cost per unit. Ratio = CM ÷ Price × 100. Break-even units = Fixed costs ÷ CM per unit.
Worked example
At a $50 price with $28 variable cost, contribution margin is $22 per unit (44% ratio). To cover $8,000 of fixed costs you need 8,000 ÷ 22 ≈ 364 units.
Frequently asked questions
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