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MER Calculator

Calculate marketing efficiency ratio using total revenue and ad spend. Enter your numbers below to get an instant result.

Updated: October 5, 2026•No sign-up required•Calculation runs in your browser

Calculate MER

Business revenue for the period.
Combined paid media spend for the same period.
MER / blended ROAS
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Revenue-to-ad-spend %
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How to use this mer calculator

Enter values from the same reporting period and use consistent definitions. Then select Calculate. The tool performs the calculation locally in your browser and shows the result immediately.

Formula

MER = Total Revenue ÷ Total Advertising Spend

Example

$50,000 in total revenue and $10,000 in advertising spend produces a 5.0x MER.

What this metric tells you

MER avoids relying only on platform attribution. It shows the relationship between total revenue and total advertising investment, which can be useful when multiple channels influence the same customer journey.

How to interpret the result

  • Use the same accounting period for revenue and ad spend.
  • MER is a blended business metric; it does not reveal which channel caused each sale.
  • Track it alongside contribution margin, new customer mix and platform-level efficiency.
Important: Calculators provide estimates based on the inputs you supply. They do not replace platform reporting, accounting records, tax advice or professional financial analysis.

Frequently asked questions

Is MER the same as ROAS?

The formula is similar, but MER normally uses total business revenue and total ad spend, while platform ROAS uses attributed revenue for a specific advertising scope.

Why can MER rise while platform ROAS falls?

Organic demand, returning customers, attribution changes or channel interactions can change the relationship between total revenue and reported platform revenue.

Should MER include every marketing cost?

Common usage focuses on media spend, but businesses may define the metric differently. Document your definition and keep it consistent.