Definition:
Return on Ad Spend (ROAS) measures the revenue generated for every dollar spent on advertising.

Formula:
ROAS = Revenue from Ads / Cost of Ads

Explanation:
ROAS evaluates the effectiveness of paid campaigns and helps determine which channels or creatives drive the highest returns.

Example:
If you spend $1,000 on ads and generate $4,000 in revenue, your ROAS is 4:1.