What is ROAS?
Return on ad spend measures how much attributed revenue advertising produces for each unit of spend. It is a focused campaign-efficiency metric. It does not automatically account for product costs, agency fees, salaries, returns, or overhead.
ROAS formulas
The basic formula is ROAS = attributed revenue ÷ ad spend. A result of 3.5× means the campaign generated 3.50 in revenue for every 1.00 spent on advertising. To add an economic check, calculate gross profit as revenue multiplied by gross margin, then subtract ad spend.
Break-even revenue ROAS can be estimated with 1 ÷ gross margin rate. For example, a 40% gross margin implies a 2.5× break-even ROAS before overhead and other costs.
Use matching inputs
- Use revenue and ad spend from the same date range, campaign scope, and currency.
- Document the attribution model and conversion window behind the revenue figure.
- Deduct refunds or cancellations consistently if they are material.
- Use a product-level margin when product mix differs substantially across campaigns.
Read ROAS alongside business outcomes
A high ROAS can still hide low scale, delayed returns, or weak customer quality. A lower ROAS may be intentional when acquiring customers with valuable repeat purchases. Review contribution profit, customer acquisition cost, payback period, and conversion quality before changing spend.