MER is one number for the whole business. It doesn't care which ad or channel got credit. It counts every sale against every dollar spent to get it.
How to calculate MER
MER = total revenue ÷ total marketing spend
$500,000 in revenue on $125,000 of marketing spend in a month is an MER of 4.0.
Pick fixed rules and keep them. Most brands use net sales for revenue and all paid media for spend. Some add agency fees, creative and influencer costs. Monthly is the usual window.
MER vs. ROAS
- ROAS is one platform's view of the sales it thinks it caused.
- MER is the business's view of everything.
ROAS helps you manage inside Meta. MER tells you whether the marketing as a whole is paying off, including the store, Amazon and repeat orders ROAS can't see.
More: Marketing efficiency ratio.
Related: ROAS, incrementality.
