> ## Documentation Index
> Fetch the complete documentation index at: https://docs.upstackdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# CM3 ROAS: Contribution Margin Return on Ad Spend

> Track CM3 ROAS for your Shopify store. Measure contribution margin return per dollar of ad spend.

<Tip>
  CM3 ROAS measures how much contribution margin (after marketing) you earn for every dollar spent on advertising.
</Tip>

## Formula

<Info>
  **CM3 ROAS** = **CM3** ÷ **Ad Spend**
</Info>

### Formula Components

| Metric                                                                                             | Definition                                    |
| -------------------------------------------------------------------------------------------------- | --------------------------------------------- |
| [**CM3 (Contribution Margin)**](/reference/metrics/orders/contribution-margin/contribution-margin) | Profit after COGS, fulfillment, and marketing |
| **Ad Spend**                                                                                       | Total advertising spend across platforms      |

| Metadata        |                                                                                                   |
| --------------- | ------------------------------------------------------------------------------------------------- |
| **Type**        | Multiplier                                                                                        |
| **Data Source** | [Shopify](/sources/shopify), [Meta Ads](/sources/facebook-ads), [Google Ads](/sources/google-ads) |
| **Aggregation** | Ratio                                                                                             |

***

## Example

Your Shopify store has **\$42,500** CM3 and spent **\$25,000** on advertising.

| Component    | Value    | Calculation         |
| ------------ | -------- | ------------------- |
| CM3          | \$42,500 | Contribution margin |
| Ad Spend     | \$25,000 | Advertising cost    |
| **CM3 ROAS** | **1.7x** | \$42,500 ÷ \$25,000 |

***

## How It Works

CM3 ROAS shows how much contribution margin your advertising generates after all variable and marketing costs. A 1.7x CM3 ROAS means every ad dollar produces \$1.70 in contribution margin—profit available to cover fixed costs.

***

## When to Use

| Scenario                        | Action                                           |
| ------------------------------- | ------------------------------------------------ |
| Measuring true ad profitability | CM3 ROAS shows margin after marketing costs      |
| Setting efficiency targets      | CM3 ROAS > 1x means positive contribution margin |
| Campaign optimization           | Focus on campaigns with highest CM3 ROAS         |
| Profitability modeling          | Use CM3 ROAS for break-even analysis             |

***

## Related Metrics

| Metric                                                     | Relationship                   |
| ---------------------------------------------------------- | ------------------------------ |
| [CM2 ROAS](/reference/metrics/orders/performance/cm2-roas) | Variable margin per ad dollar  |
| [CM4 ROAS](/reference/metrics/orders/performance/cm4-roas) | Operating profit per ad dollar |
| [ROAS](/reference/metrics/orders/performance/roas)         | Revenue per ad dollar          |

[See all Performance metrics →](/reference/metrics/orders/performance)