Return on Ad Spend (ROAS) is a marketing metric that measures the revenue generated from advertising campaigns relative to the amount spent on those campaigns. ROAS is typically calculated as a ratio of revenue to advertising spend, expressed as a percentage or a multiple.

For example, if an ad campaign generated $10,000 in revenue and cost $2,000 to run, the ROAS would be calculated as follows:

ROAS = ($10,000 revenue / $2,000 ad spend) = 5

In this example, the ROAS is 5, indicating that the campaign generated $5 in revenue for every $1 spent on advertising.

ROAS is an important metric for marketers as it provides insights into the effectiveness and efficiency of their advertising campaigns. A higher ROAS generally indicates that a campaign is generating more revenue for every dollar spent, while a lower ROAS may suggest that a campaign needs to be revised or optimized to improve its performance.