> ## 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.

# Trial Converted Cost: Ad Spend per Paid Conversion

> Calculate advertising cost per trial-to-paid conversion. Your true customer acquisition cost.

<Tip>
  Trial Converted Cost measures your advertising spend per trial that converts to a paid subscription.
</Tip>

## Formula

<Info>
  **Trial Converted Cost** = **Ad Spend** ÷ **Trial Converted**
</Info>

### Formula Components

| Metric                                                                       | Definition                                         |
| ---------------------------------------------------------------------------- | -------------------------------------------------- |
| [**Ad Spend**](/reference/metrics/advertising/blended/blended-spend)         | Total advertising cost from connected ad platforms |
| [**Trial Converted**](/reference/metrics/funnel/conversions/trial-converted) | Count of trials converted to paid                  |

| Metadata        |                         |
| --------------- | ----------------------- |
| **Type**        | Currency                |
| **Data Source** | [Upstack Pixel](/pixel) |
| **Aggregation** | Ratio                   |

***

## Example

You spent **\$5,000** on Meta ads in January and drove **107 trial conversions**.

| Metric               | Value   | Notes                    |
| -------------------- | ------- | ------------------------ |
| Ad Spend             | \$5,000 | Monthly advertising cost |
| Trial Converted      | 107     | Paid conversions         |
| Trial Converted Cost | \$46.73 | Cost per paying customer |

***

## How It Works

This metric divides your total ad spend by the number of trial conversions to calculate your true customer acquisition cost (CAC). This represents the full cost of acquiring a paying customer through your trial funnel.

***

## When to Use

| Scenario              | Action                                              |
| --------------------- | --------------------------------------------------- |
| CAC optimization      | Find channels with lowest customer acquisition cost |
| LTV/CAC analysis      | Compare CAC against customer lifetime value         |
| Channel profitability | Identify most efficient acquisition sources         |
| Budget planning       | Forecast spend needed for growth targets            |

***

## Related Metrics

| Metric                                                                               | Relationship                        |
| ------------------------------------------------------------------------------------ | ----------------------------------- |
| [Trial Converted](/reference/metrics/funnel/conversions/trial-converted)             | The denominator in this calculation |
| [Trial Converted Value](/reference/metrics/funnel/conversions/trial-converted-value) | Revenue from conversions            |
| [Trial Started Cost](/reference/metrics/funnel/conversions/trial-started-cost)       | Cost at trial start stage           |

[See all Conversions metrics →](/reference/metrics/funnel/conversions)