Your platform says the campaign worked. How much of that was going to happen anyway?

Platforms grade their own homework. This shows the gap between reported ROAS and likely incremental ROAS, the number a CFO actually cares about. Built by an operator who allocates large media budgets on incrementality and contribution margin, not platform dashboards.

Monthly spend on the channel ($)

Platform-reported ROAS

How much of this channel's traffic is branded or retargeting? Clicks from people who already knew you. The higher this is, the more the platform is claiming demand you already owned. 40% Attribution window aggressiveness View-through counting, long click windows, and last-touch greed all inflate credit. Moderate Contribution margin on those sales (%) After product cost, shipping, and fulfillment. ROAS without margin is applause without revenue. 45%

Estimated incremental ROAS

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Reported revenue—

Likely incremental revenue—

Incremental profit after margin—

This is a directional model, not a measurement. The real answer comes from geo holdouts, incrementality tests, and media-mix modeling. But if this toy math makes you nervous, that is the point: run the test. Platform-reported ROAS is a sales pitch until it is validated.