Return on ad spend (ROAS)
Return on ad spend (ROAS) is the ratio of return to cost for an ad campaign. It allows for easy interpretability around how much a profit is being driven by a campaign. A key KPI in the digital marketing world, a ROAS of 5:1 is interpreted as every dollar spent on said campaign provides a return of $5, on average.
ROAS = revenue from ad spend / cost of campaign