What is MER (Marketing Efficiency Ratio)?
Marketing Efficiency Ratio (MER) measures total revenue relative to total marketing spend — including not just ads, but also email platforms, SMS tools, influencer fees, agency costs, and any other marketing expenditure.
Why It Matters
MER gives you a more comprehensive view than ROAS because it accounts for all marketing costs, not just ad spend. As brands invest more in organic, email, and influencer channels, MER becomes a better strategic metric.
How to Calculate It
MER = Total Revenue ÷ Total Marketing Spend
MER vs. ROAS
| Metric | Numerator | Denominator |
|---|---|---|
| ROAS | Revenue from ads | Ad spend only |
| Blended ROAS | Total revenue | Total ad spend |
| MER | Total revenue | All marketing costs |
Using MER Strategically
MER is most useful for answering: “Overall, is my marketing investment generating efficient growth?” Track it alongside channel-level metrics for a complete picture.