How to use this calculator
- Enter your ad spend for a period, such as a campaign or a month.
- Enter the revenue from ads in the same period, as reported by your ad platform or store analytics.
- Optionally add your profit margin before ads to compare your ROAS with your break-even ROAS and see the profit or loss from your ads.
ROAS formula
ROAS = Revenue from ads ÷ Ad spend
ROAS is written in three equivalent ways: as a ratio (3.5), as a ratio to one (3.5:1) or as a percentage (350%). To turn a ratio into a percentage, multiply by 100. ROAS is the inverse of ACoS, so a ROAS of 3.5 is an ACoS of 1 ÷ 3.5 ≈ 28.6% (see the ACoS calculator).
Worked example
You spend $1,000 on ads in a month and they bring in $3,500 of revenue.
- ROAS: $3,500 ÷ $1,000 = 3.5, or 350%
- ACoS: $1,000 ÷ $3,500 ≈ 28.6%
With a 40% margin before ads, that revenue leaves $3,500 × 40% = $1,400 of profit before ads. After the $1,000 of ad spend, you keep $400. Your break-even ROAS is 1 ÷ 0.40 = 2.5, so a ROAS of 3.5 is comfortably profitable.
Is your ROAS profitable?
ROAS only measures revenue. Whether it makes money depends on your margin: the same ROAS can be profitable for one product and a loss for another. This table shows the profit or loss from $1,000 of ad spend:
| ROAS | At 30% margin | At 50% margin |
|---|---|---|
| 2.0 | −$400.00 | $0.00 |
| 3.0 | −$100.00 | $500.00 |
| 4.0 | $200.00 | $1,000.00 |
| 5.0 | $500.00 | $1,500.00 |
To find the exact ROAS where your ads stop losing money, including shipping, payment fees and returns, use the break-even ROAS calculator. To find the ROAS you need for a profit goal, use the target ROAS calculator.
ROAS vs ROI
ROAS compares revenue with ad spend. ROI (return on investment) compares profit with the full cost, so it includes product costs, fees and overhead. ROAS is useful for comparing campaigns quickly. Contribution after ads still has to cover fixed overhead and taxes before the business makes a net profit.
Frequently asked questions
What is ROAS?
ROAS (return on ad spend) is the revenue your advertising generates for every unit of currency you spend on it. A ROAS of 4 means $4 of revenue for every $1 of ad spend.
How do you calculate ROAS?
Divide the revenue attributed to your ads by what you spent on them: ROAS = ad revenue ÷ ad spend. $3,500 of revenue from $1,000 of ads is a ROAS of 3.5.
How do I convert ROAS to a percentage?
Multiply it by 100. A ROAS of 3.5 is 350%. Some reports show ROAS as a ratio (3.5 or 3.5:1) and others as a percentage (350%); they mean the same thing.
What is a good ROAS?
There is no universal good ROAS, because it depends on your profit margin. Any ROAS above your break-even ROAS (1 ÷ your margin before ads) makes money. With a 40% margin you break even at 2.5; with a 20% margin you need 5.0.
Is ROAS the same as ROI?
No. ROAS compares revenue with ad spend. ROI compares profit with the total investment, so it accounts for product costs, fees and other expenses. A campaign can have a ROAS above 1 and still lose money once those costs are included.
What is the difference between ROAS and ACoS?
ACoS is the inverse of ROAS: ACoS = ad spend ÷ ad sales = 1 ÷ ROAS. A ROAS of 4 equals an ACoS of 25%. Amazon Ads reports ACOS by default, while platforms such as Google Ads and Meta report ROAS or conversion value per cost.
Why doesn't my ad platform's ROAS match my store's numbers?
Ad platforms attribute sales with their own attribution windows and models, may count conversions that another channel also claims, and often report conversion value including tax or shipping. Check which revenue figure your ROAS uses before comparing it with your break-even ROAS.
By the SellerUtils team · Last updated October 1, 2026. Results are estimates for planning and are not financial advice.