Contribution Margin Calculator
Find the contribution margin per unit and as a percentage after variable costs, useful for pricing and break-even decisions.
Your results
Calculation breakdown
- Contribution margin
- Selling price − Variable cost per unit
- CM ratio
- (Contribution margin ÷ Selling price) × 100
Worked example
A candle maker sells each candle for $50 with $30 of variable costs, giving a $20 contribution margin per unit, a 40% CM ratio.
Assumptions
- Variable costs should only include costs that scale with each unit sold.
- Fixed costs are not included in this per-unit calculation.
- Use the result alongside total fixed costs to estimate a break-even point.
How this calculator works
Contribution margin is the amount each sale contributes towards covering fixed costs once variable costs are removed. Enter your selling price and variable cost per unit to see the margin in dollars and as a percentage.
Frequently asked questions
What is a variable cost?
A cost that changes directly with sales volume, such as materials, packaging or sales commissions, unlike fixed costs like rent.
How does this help with break-even?
Dividing total fixed costs by the contribution margin per unit shows how many units you need to sell to break even.
Why does contribution margin matter for pricing?
A low or negative contribution margin means each extra sale is not covering its own variable cost, let alone fixed overheads.
Results are estimates only and are not financial, tax, legal or credit advice.