> ## 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.

# Blended Cost Per Comment: Ad Engagement Efficiency

> Measure the cost per comment on your ads across Meta, Google, and TikTok. Optimize engagement spending with this aggregated efficiency metric.

<Tip>
  The cost per comment on your ads, aggregated across all advertising platforms.
</Tip>

## Formula

<Info>
  **Blended Cost Per Comment** = **Blended Spend** ÷ **Blended Comments**
</Info>

### Formula Components

| Metric                                                                                             | Definition                      |
| -------------------------------------------------------------------------------------------------- | ------------------------------- |
| [**Blended Spend**](/reference/metrics/advertising/blended/blended-spend/blended-spend)            | Total ad spend across platforms |
| [**Blended Comments**](/reference/metrics/advertising/blended/blended-engagement/blended-comments) | Total comments across platforms |

| Metadata        |                                                                                                     |
| --------------- | --------------------------------------------------------------------------------------------------- |
| **Type**        | Currency                                                                                            |
| **Data Source** | [Meta Ads](/sources/facebook-ads), [Google Ads](/sources/google-ads), [TikTok Ads](/sources/tiktok) |
| **Aggregation** | Ratio                                                                                               |

***

## Example

Your campaigns spent **\$2,540** and generated **127 comments**—yielding **\$20.00 cost per comment**. Meta drove comments at \$17.65 while TikTok cost \$26.67 per comment.

***

## How It Works

Divides total ad spend by total comments across all platforms. Lower values mean more cost-efficient comment generation.

***

## When to Use

| Scenario              | Action                                               |
| --------------------- | ---------------------------------------------------- |
| Engagement efficiency | Compare cost to acquire comments across campaigns    |
| Budget optimization   | Identify platforms with lower engagement costs       |
| Creative testing      | Measure which ads drive cost-efficient conversations |

***

## Related Metrics

| Metric                                                                                                               | Relationship                  |
| -------------------------------------------------------------------------------------------------------------------- | ----------------------------- |
| [Blended Spend](/reference/metrics/advertising/blended/blended-spend/blended-spend)                                  | Numerator (total spend)       |
| [Blended Comments](/reference/metrics/advertising/blended/blended-engagement/blended-comments)                       | Denominator (total comments)  |
| [Blended Cost Per Engagement](/reference/metrics/advertising/blended/blended-engagement/blended-cost-per-engagement) | Broader engagement efficiency |

[See all Blended Engagement metrics →](/reference/metrics/advertising/blended/blended-engagement)