Return on ad spend (ROAS) is a ratio of Gross Revenue to advertising spent during a campaign. It is a metric used to determine the effectiveness of advertising.

For example, a company has a revenue of $45,000. The cost of the marketing campaign is $9,000.

ROAS = 45,000 / 9,000 = 9

The formula is: Return on Ad Spend = Gross Revenue / Cost of Campaign