*Gross Margin* is the Gross Profit as a percentage of Net Sales. The calculation of the Gross Profit is: Sales minus Cost of Goods Sold. The *Cost of Goods Sold* consists of the fixed and variable product costs, but it excludes all of the selling and administrative expenses.

*Contribution Margin* is Net Sales minus the *variable* product costs and the *variable* period expenses. The *Contribution Margin Ratio* is the Contribution Margin as a percentage of Net Sales.

Let's illustrate the difference between gross margin and contribution margin with the following information: company had Net Sales of $600,000 during the past year. Its inventory of goods was the same quantity at the beginning and at the end of year. Its Cost of Goods Sold consisted of $120,000 of variable costs and $200,000 of fixed costs. Its selling and administrative expenses were $40,000 of variable and $150,000 of fixed expenses.

The company's *Gross Margin* is: Net Sales of $600,000 minus its Cost of Goods Sold of $320,000 ($120,000 + $200,000) for a Gross Profit of $280,000 ($600,000 - $320,000). The Gross Margin or Gross Profit Percentage is the Gross Profit of $280,000 divided by $600,000, or 46.7%.

The company's *Contribution Margin* is: Net Sales of $600,000 minus the variable product costs of $120,000 and the variable expenses of $40,000 for a Contribution Margin of $440,000. The Contribution Margin Ratio is 73.3% ($440,000 divided by $600,000).