ROAS to MER Converter

Turn platform-reported ROAS into your true blended marketing efficiency ratio.

Currency

Total revenue (all sources)

From your store / backend, not the ad platform.

Total marketing spend

Everything you paid across channels.

Platform-reported ROAS

The blended number the pixels claim.

True blended MER

4.00×

Total revenue ÷ total spend

Platform-claimed revenue

$375,000

ROAS × spend

Over-claim vs. reality

25.0%

How much pixels overstate

Attribution gap

$75,000

Claimed − real revenue

Your platforms claim 5.00× but blended MER is only 4.00× — about 25.0% of over-reporting. Scale to the MER, not the pixel.

MER (Marketing Efficiency Ratio) counts total revenue against total spend, so it can't double-count the way per-platform ROAS does.

About this calculator

Convert inflated, pixel-attributed ROAS into blended MER (total revenue ÷ total spend) so you scale budget on reality instead of double-counted platform numbers.

Everything runs in your browser — nothing you type is sent anywhere or stored. Use it to sanity-check a plan, pressure-test a channel, or brief a team before you commit budget.