Blended CPA measures the average cost to acquire each purchase conversion across all your advertising channels combined.
Blended CPA = Blended Spend ÷ Blended Purchases
| Metric | Definition |
|---|
| Blended Spend | Total advertising spend across all connected platforms |
| Blended Purchases | Total attributed purchase conversions across all channels |
| Metadata | |
|---|
| Type | Currency |
| Data Source | Meta Ads, Google Ads, TikTok Ads |
| Aggregation | Ratio |
Example
Your store spent $12,500 across all advertising channels in March and generated 250 attributed purchases.
| Channel | Spend | Purchases | Channel CPA |
|---|
| Meta | $6,000 | 150 | $40.00 |
| Google | $4,000 | 70 | $57.14 |
| TikTok | $2,500 | 30 | $83.33 |
| Blended | $12,500 | 250 | $50.00 |
How It Works
Blended CPA aggregates total spend and total attributed purchases from all connected ad platforms, then calculates the average cost per conversion. This gives you a single efficiency metric across your entire paid media mix rather than evaluating each channel separately.
When to Use
| Scenario | Action |
|---|
| Setting overall acquisition targets | Compare blended CPA to customer lifetime value |
| Budget allocation decisions | Identify if total spend is generating efficient conversions |
| Monthly performance reviews | Track acquisition cost trends across all channels |
| Scaling paid media | Monitor if efficiency holds as you increase total spend |
| Metric | Relationship |
|---|
| Blended Spend | Numerator — total ad spend across platforms |
| Blended Purchases | Denominator — total attributed purchases |
| Blended ROAS | Inverse efficiency metric measuring revenue return |
