Blended ROAS / MER Calculator
Calculate blended ROAS — also called Marketing Efficiency Ratio (MER) — across your whole business, not just one ad platform.
Formula
MER (Blended ROAS) = Total Business Revenue ÷ Total Marketing Spend
This is the exact same arithmetic as the ROAS Calculator — "MER" and "blended ROAS" both just mean applying that ratio at the whole-business level instead of to one platform's self-reported numbers. The formula isn't different; the inputs are.
Platform-reported ROAS (Google Ads, Meta Ads, etc.) can overstate results because platforms often take credit for the same conversion through different attribution models, and ignore channels they can't see. MER avoids that by starting from total revenue and total spend.
Worked Example
A business generates $120,000 in total revenue in a month and spends $20,000 across all paid channels combined. MER = $120,000 ÷ $20,000 = 6.0. This may differ meaningfully from what each individual platform reports.