Return on Ad Spend (ROAS) shows how much revenue each euro invested in advertising generated.
ROAS stands for Return on Ad Spend. This metric compares the revenue generated by advertising to the expenses incurred for those campaigns.
ROAS is expressed as a multiplier: A ROAS of 5 or 500% means that every euro invested generated five euros in revenue.
The formula for ROAS is: advertising revenue divided by advertising expenses.
ROAS is a key metric in performance-based marketing and provides insight into how much revenue was generated relative to advertising expenses.
As soon as it became possible in digital marketing to precisely measure advertising expenditures and the resulting revenue, the need arose to turn this into a key metric. With the rise of performance marketing, ROAS became a key metric and the standard in advertising platforms such as Google Ads and on social media. These platforms typically report ROAS automatically and even use it as a target for automated bidding strategies.
Every advertising expenditure should be justifiable. ROAS provides the justification—or the lack thereof—in a single number. It shows how much revenue campaigns generate relative to their advertising costs and makes it possible to compare different initiatives.
This enables informed budget management: What works can be scaled up, while initiatives with low ROAS can be reviewed and, if necessary, paused. In companies where every euro counts, ROAS is a practical management and control tool that grounds advertising in hard numbers rather than gut feelings.
ROAS measures revenue, not profit. A high value can be misleading if other costs are high, which is why it must always be interpreted in relation to your own margin.
Depending on the tracking and attribution model, ROAS may only account for previous touchpoints to a limited extent. Accurate attribution is particularly difficult in cases of long decision-making phases or offline conversions, which limits the significance of ROAS.
A retailer spends €4,000 per month on Shopping ads and generates €20,000 in revenue. The ROAS is 5.
A second campaign generates only €6,000 in revenue at a cost of €3,000. The ROAS is 2.
The retailer reduces the budget for the weaker campaign and allocates it to the stronger one. At the same time, they assess whether a ROAS of 2 is profitable given their profit margin, since a high number alone does not guarantee a profit.