Contribution Margin Calculator

Quick answer

The contribution margin calculator works out how much each unit sold contributes to covering fixed costs and profit, the contribution margin ratio, total contribution and the profit after fixed costs.

$
$
$
Contribution margin per unit
$ 20.00
Contribution margin ratio
40 %
Total contribution margin
$ 20,000.00
Profit (after fixed costs)
$ 5,000.00
Break-even units
750

Contribution margin is the money left from each sale after paying the variable costs of producing it. It is the key number for break-even analysis, pricing and deciding which products to push.

How to use the Contribution Margin Calculator

  1. Selling price per unit
  2. Variable cost per unit
  3. Number of units
  4. Fixed costs

Results update as you type, and every field accepts the units shown in its menu.

How it works

Enter the selling price and variable cost per unit, the number of units and your fixed costs.

Inputs explained

Field What to enter
Selling price per unit Amount in your currency
Variable cost per unit Amount in your currency
Number of units A number
Fixed costs Amount in your currency

What each result means

  • Contribution margin per unit = [Selling price per unit] – [Variable cost per unit]
  • Contribution margin ratio = ([Selling price per unit] – [Variable cost per unit])÷[Selling price per unit]×100
  • Total contribution margin = ([Selling price per unit] – [Variable cost per unit])×[Number of units]
  • Profit (after fixed costs) = [Total contribution margin] – [Fixed costs]
  • Break-even units = ceil([Fixed costs]÷([Selling price per unit] – [Variable cost per unit]) – 0.000001)

Example values

How the main result changes when Selling price per unit changes and everything else stays at the example values above:

Selling price per unit Contribution margin ratio (%)
25 -20
37.5 20
50 40
62.5 52
75 60
100 70

Formula

Contribution margin per unit = price − variable cost per unit CM ratio = CM ÷ price Total contribution = CM × units; profit = total contribution − fixed costs

Worked example

Inputs: Selling price per unit: $50; Variable cost per unit: $30; Number of units: 1,000; Fixed costs: $15,000.
Results: Contribution margin per unit = $20.00; Contribution margin ratio = 40 %; Total contribution margin = $20,000.00; Profit (after fixed costs) = $5,000.00; Break-even units = 750.

Frequently asked questions

What is a good contribution margin ratio?

It depends on the industry; higher ratios leave more to cover fixed costs.

How is contribution margin different from gross margin?

Contribution margin subtracts only variable costs; gross margin subtracts all cost of goods sold.

Can contribution margin be negative?

Yes, if variable costs exceed the price, as each sale then loses money.

Sources

  1. Corporate Finance Institute: financial ratios

Cite this calculator

Speedy Calculator. (2026). Contribution Margin Calculator. Speedy Calculator. https://speedycalculator.com/calculators/finance/contribution-margin/