How do I convert ACoS to ROAS on Amazon?

Divide 100 by your ACoS percentage to get ROAS. An ACoS of 20% gives ROAS = 100 / 20 = 5. An ACoS of 25% gives ROAS = 100 / 25 = 4. An ACoS of 40% gives ROAS = 100 / 40 = 2.5. To convert in the other direction, divide 100 by your ROAS to get ACoS: a ROAS of 6 gives ACoS = 100 / 6 = approximately 16.7%.

Does Amazon report both ACoS and ROAS in Campaign Manager?

Yes. Amazon's Campaign Manager reports both ACoS and ROAS in the campaign performance columns. By default, Campaign Manager shows ACoS prominently, but ROAS is available as an optional column that can be added via the column customisation panel. Both figures update in real time as campaign data is processed, and both are available at the campaign, ad group and keyword level for granular analysis.

Which is better to use for Amazon PPC: ACoS or ROAS?

Both are equally valid because they describe the same underlying performance. ACoS is more commonly used in the Amazon seller community and is the default metric shown in Seller Central, making it the more practical choice for sellers managing Amazon campaigns specifically. ROAS is more portable across advertising platforms and may be preferable if you need to compare Amazon performance against Google, Meta or other channel performance in a unified report. Pick one, build your benchmarks around it, and convert to the other when needed for communication purposes.

What is the difference between ACoS and ROAS?

ACoS, Advertising Cost of Sales, and ROAS, Return on Ad Spend, are the two most widely used metrics for measuring Amazon PPC campaign efficiency. Many sellers encounter both and are unsure which to use, whether they tell the same story, or when one is preferable to the other. The short answer is that they are mathematically equivalent: one is the inverse of the other, and knowing the value of one gives you the value of the other instantly. The longer answer is that they frame the same information differently, and that framing matters depending on the decision you are trying to make. Both ACoS and ROAS use the same two inputs: ad spend and ad-attributed revenue. ACoS divides spend by revenue and expresses the result as a percentage. ROAS divides revenue by spend and expresses the result as a ratio. The conversion between them is straightforward: ROAS = 100 / ACoS (when ACoS is expressed as a percentage). Equivalently, ACoS = 100 / ROAS. This means any ACoS figure can be converted to ROAS in one step and vice versa. An ACoS of 20% is a ROAS of 5. An ACoS of 33% is a ROAS of approximately 3. An ACoS of 10% is a ROAS of 10. The directional relationship between the two is inverted. A lower ACoS indicates better campaign efficiency: you are spending less of your ad revenue on advertising. A higher ROAS indicates better campaign efficiency: you are generating more revenue per unit of ad spend. When communicating performance targets, be careful about the direction: telling someone to increase ACoS is bad, while telling them to decrease ROAS is also bad. Always specify which metric and which direction constitutes improvement. The choice between ACoS and ROAS is largely one of context and convention rather than accuracy. ACoS is the native Amazon Advertising metric: it appears prominently throughout Seller Central's Campaign Manager interface and is the metric most Amazon-focused sellers, agencies and courses use. If you manage your business entirely within the Amazon ecosystem, ACoS is likely the more familiar and useful convention for your team. ROAS is the dominant metric in Google Ads, Meta Ads, TikTok Ads and most other digital advertising platforms. If you manage advertising across multiple channels, use an agency with cross-platform expertise, or report to stakeholders who are more familiar with the broader digital advertising landscape, ROAS may be the clearer communication tool. The underlying efficiency information is identical: use whichever metric your audience understands instinctively and build consistent benchmarks around that choice. Neither ACoS nor ROAS tells you whether advertising is profitable without knowing your product's margin. Both metrics measure the ratio between spend and attributed revenue, but profitability requires you to compare that ratio against the margin available to absorb advertising costs. Break-even ACoS equals your net margin percentage. Break-even ROAS equals 1 divided by your net margin as a decimal. A product with a 25% net margin has a break-even ACoS of 25% and a break-even ROAS of 4. Both metrics also measure only ad-attributed revenue, which excludes organic sales driven by ad-funded ranking gains. A campaign that appears to have a poor ACoS or low ROAS may still be creating significant value if it is driving keywords to higher organic positions where they generate organic sales. This limitation is why TACoS, which includes organic revenue in its calculation, is a valuable complement to both ACoS and ROAS for making strategic advertising investment decisions.

ACoS and ROAS both measure Amazon PPC efficiency but from opposite perspectives. Learn how they relate, which to focus on and how to convert between them.