What is ROAS?
ROAS is the most common efficiency number in paid media. It answers a simple question: for each dollar spent on ads, how many dollars of revenue came back?
Simple doesn't mean settled. Which revenue counts, over what window, before or after returns, and credited by which attribution model are all choices. Two teams can report different ROAS for the same campaign and both be calculating correctly.
How do you calculate ROAS?
ROAS = revenue attributed to ads / ad spend. If a campaign drives $50,000 in revenue on $10,000 of spend, its ROAS is 5, often written 5:1 or 500%.
| Choice | Common options | Why it matters |
|---|---|---|
| Revenue | Gross order value, or net of returns and discounts | Returns can turn a strong ROAS into a loss |
| Attribution | Platform-reported, last-click, or modeled | Platforms each count the same sale |
| Window | 1, 7, or 28 days after a click or view | Longer windows credit more sales to the ads |
| Spend | Media only, or media plus fees and production | Fuller costs give a more honest number |
Breakeven ROAS
Breakeven ROAS = 1 / gross margin. With a 40% gross margin, ads need a ROAS of 2.5 just to cover the cost of the product sold. Anything below that loses money on every sale it drives.
What is an example of ROAS?
Two campaigns, two margins
Campaign A sells accessories with a 60% margin at a ROAS of 3. Campaign B sells electronics with a 20% margin at a ROAS of 4.
B looks better on ROAS. But A's breakeven is about 1.7 and B's is 5, so A is profitable and B loses money on each sale. Ranking by ROAS alone would move budget the wrong way.
ROAS vs. ROI vs. MER
| ROAS | ROI | MER | |
|---|---|---|---|
| Formula | Attributed revenue / ad spend | (Profit − investment) / investment | Total revenue / total marketing spend |
| Counts costs beyond media | No | Yes | No |
| Level | Campaign, channel, or ad | Any investment | The whole business |
| Best for | Comparing ads within a channel | Deciding if spend is profitable | Checking overall efficiency |
Why does ROAS matter, and where does it mislead?
ROAS is fast, comparable, and available in every ad platform, which is why bidding systems optimize to it. The same features make it easy to over-trust.
- It isn't causal. Attributed revenue includes sales that would have happened anyway, especially for retargeting and branded search.
- It isn't profit. Without margin, a high ROAS can still lose money.
- It's an average. The ROAS of the next dollar is usually lower. That's marginal ROAS, and it's what budget decisions need.
- It ignores returns. Platforms optimize on checkout value, so products that get sent back can look like winners.
How does Alli do this?
Alli by PMG's Semantic Layer sets how ROAS, CPA, conversion rate, and cost per lead are calculated one time, so ROAS means the same thing in every dashboard, deck, and market. Reports from different teams match, and reviews stop opening with whose number is right.
For planning, Alli Scenario Planner shows minimum and maximum spend for every channel, with predicted revenue and ROAS, so teams can see where each channel sits on its diminishing-return curve before they move budget.
Explore Alli Semantic LayerROAS FAQ
What is a good ROAS?
It depends on your margins. A good ROAS is comfortably above your breakeven ROAS, which is one divided by gross margin. A business with a 25% margin needs at least 4 to break even, while one with a 75% margin needs about 1.3.
What is the difference between ROAS and ROI?
ROAS compares revenue with ad spend. ROI compares profit with the full investment, so it includes product and other costs. ROAS can be high while ROI is negative.
Why is platform ROAS higher than my actual results?
Each platform credits itself for any sale it touched, using its own window. When several platforms touch one sale, they all count it, so platform totals can add up to more revenue than the business made.
Is ROAS a percentage or a ratio?
Either. A ROAS of 4 can be written as 4, 4:1, or 400%. All mean four dollars of revenue for each dollar of ad spend.
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