Post-iOS14 Blended Attribution Modeler

Correct platform over-reporting into a true blended ROAS you can bank on.

Currency

Platform-claimed revenue

Sum of revenue all ad platforms report.

Actual revenue (backend)

From your store / finance system.

Total ad spend

Platform-reported ROAS

5.25×

Claimed revenue ÷ spend

True blended ROAS

3.75×

Real revenue ÷ spend

Over-reporting

40.0%

How much platforms overstate

Double-counted revenue

$120,000

Claimed − actual

Your platforms claim 5.25× but true blended ROAS is 3.75× — about 40.0% of over-reporting from overlapping attribution. Apply a ~29% haircut to platform numbers when you scale.

Every platform takes credit for the same conversion, so summed platform revenue routinely exceeds real revenue. Blended, backend-anchored ROAS is the honest number.

About this calculator

Compare platform-claimed revenue against real backend revenue to expose double-counting, then compute the corrected blended ROAS and over-reporting factor.

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.