> ## 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.

# Cost per Add to Wishlist: Wishlist Acquisition Efficiency

> Track your cost per add to wishlist event. Measure how efficiently your ad spend drives wishlist engagement and product interest signals.

<Tip>
  Cost per Add to Wishlist measures how much you spend on advertising to generate one wishlist addition.
</Tip>

## Formula

<Info>
  **Cost per Add to Wishlist** = **Channel Spend** ÷ **Add to Wishlist Events**
</Info>

### Formula Components

| Metric                                                                             | Definition                                                                          |
| ---------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| **Channel Spend**                                                                  | Total advertising spend across your connected ad channels                           |
| [**Add to Wishlist Events**](/reference/metrics/funnel/engagement/add-to-wishlist) | Total times visitors added products to their wishlist, tracked by the Upstack pixel |

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

***

## Example

Your store spent **\$2,500** on advertising last week and generated **500 add to wishlist events**.

| Metric                       | Value      |
| ---------------------------- | ---------- |
| Channel Spend                | \$2,500    |
| Add to Wishlist Events       | 500        |
| **Cost per Add to Wishlist** | **\$5.00** |

Each wishlist addition cost \$5.00 in ad spend.

***

## How It Works

This metric divides your total advertising spend by the number of add to wishlist events tracked by the Upstack pixel. Lower values indicate more efficient spend — you're generating product interest at a lower cost. Wishlist additions signal high purchase intent, making this a valuable upper-funnel efficiency indicator.

***

## When to Use

| Scenario                       | Action                                                               |
| ------------------------------ | -------------------------------------------------------------------- |
| Cost per wishlist add rising   | Review audience targeting and creative performance                   |
| Testing new ad creatives       | Compare wishlist acquisition costs across variants                   |
| Evaluating campaign efficiency | Benchmark against other engagement costs (add to cart, view content) |
| Planning retargeting budget    | Use wishlist audience size and cost to forecast spend                |

***

## Related Metrics

| Metric                                                                              | Relationship                                 |
| ----------------------------------------------------------------------------------- | -------------------------------------------- |
| [Add to Wishlist](/reference/metrics/funnel/engagement/add-to-wishlist)             | The event count used as the denominator      |
| [Add to Wishlist Value](/reference/metrics/funnel/engagement/add-to-wishlist-value) | Total monetary value of wishlist additions   |
| [Cost per Add to Cart](/reference/metrics/funnel/engagement/cost-per-add-to-cart)   | Similar efficiency metric for cart additions |

[See all Engagement metrics →](/reference/metrics/funnel/engagement)