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Free ROAS and break-even ROAS calculator
Calculate return on ad spend, ROAS percentage, and break-even ROAS. Explore an example and see why revenue-based ROAS is different from profit.
Use revenue left after variable costs, before advertising and fixed overhead, as a percentage of revenue. Use the same currency and reporting period for spend and revenue; changing currency only changes the label.
- Return on ad spend
- 4×
- ROAS percentage
- 400%
- Break-even ROAS before overhead
- 2.5×
- Contribution after ad spend
- $600.00
Starts with illustrative values. Calculator inputs stay in this browser and are not saved or submitted. Results exclude fixed overhead and depend on the values you enter.
How to calculate ROAS
Return on ad spend compares the revenue attributed to advertising with the amount spent on those ads. Divide attributed revenue by ad spend to express it as a multiple. Multiply the result by 100 to express it as a percentage.
ROAS = attributed revenue ÷ ad spend. For example, 4,000 in attributed revenue divided by 1,000 in ad spend is 4×, or 400%. That means four units of attributed revenue for each unit spent on advertising.
Google’s Target ROAS documentation also expresses the relationship as conversion value divided by cost. Check what your conversion values represent: revenue, a fixed lead value, and profit-based values are different inputs.
How break-even ROAS depends on margin
A revenue-based ROAS of 1× only matches revenue to ad spend. It does not cover the cost of delivering the product or service. To estimate the point where contribution covers advertising, use the share of revenue left after variable costs and before ads.
Break-even ROAS before overhead = 1 ÷ contribution margin as a decimal. At a 40% margin, the calculation is 1 ÷ 0.40 = 2.5×. With the example above, 4,000 × 0.40 − 1,000 leaves 600 after variable costs and advertising, before fixed overhead.
| Contribution margin before ads | Break-even ROAS |
|---|---|
| 20% | 5× |
| 40% | 2.5× |
| 50% | 2× |
Use a margin that reflects the costs relevant to your business, such as fulfillment and payment fees. This simplified estimate excludes fixed overhead and assumes the entered attributed revenue is the revenue you want to evaluate. It does not establish that the ads caused those sales.
ROAS is different from profit and ROI
ROAS uses advertising spend as its denominator and attributed revenue as its numerator. Profit also depends on costs. An ROI calculation needs an explicitly defined investment and return. Avoid describing a 400% ROAS as a 400% profit margin or an ROI result.
There is no single good ROAS for every advertiser. Product margins, lead quality, repeat purchases, attribution, refunds, and the reporting window all affect what a result means. Use your own economics and an agreed measurement method.
Before comparing Google Ads and Meta Ads
- Use the same currency and a comparable reporting period.
- Check whether conversion values represent actual revenue or assigned values.
- Review attribution settings and conversion delays in each platform.
- Avoid adding platform-reported revenue together unless you have checked for overlapping attribution.
For a more complete review, follow the Google Ads and Meta Ads audit checklist. Lethir’s connected reports and AI-assisted analysis can help organize the campaign questions that follow.