Marketing Efficiency Ratio (MER)
Definition
Marketing Efficiency Ratio (MER): MER (Marketing Efficiency Ratio) is total revenue divided by total marketing spend across all paid channels. It is the DTC operator's version of blended ROAS and the most cited attribution-agnostic metric since iOS 14.5.
Frequently Asked Questions
Is MER the same as blended ROAS?
Yes. MER is the DTC operator vocabulary; blended ROAS is the paid-media vocabulary. Both equal total revenue divided by total paid spend.
Does MER include organic revenue?
Yes — the numerator is total revenue across every source. Only paid spend is in the denominator, which is why MER captures the halo effect of paid ads on organic demand.
What MER do I need to be profitable?
Break-even MER = 1 / (gross margin - variable cost percentage). A brand with 50% gross margin and 15% variable costs needs MER above roughly 2.86x to break even on contribution.