Attribution Gap Calculator
Last-touch attribution misstates channel performance by an estimated 40 to 60 percent. This calculator estimates how much of your paid spend is likely misattributed, so you can see the size of the blind spot before you fix it.
With $100,000/mo across 4 channels on last-touch attribution, roughly $40,000–$60,000 of paid spend is likely credited to the wrong channel each month. That's $480,000–$720,000 a year of decisions made on numbers that lie.
A Growth Audit rebuilds your attribution against a holdout so you can see the real numbers — and reallocate budget with confidence.
How the estimate is built.
Independent holdout studies across paid social, paid search, and organic have consistently shown that last-touch attribution misassigns roughly 40 to 60 percent of credit in most funnels. The error is largest for upper-funnel channels and smallest for branded search. This calculator applies a per-model misattribution factor to your monthly spend to estimate the size of that gap.
- None · 0.60
- Last-touch · 0.50
- First-touch · 0.45
- Multi-touch · 0.20
The low/high band reflects a ±10 percentage-point uncertainty around the central factor, clamped to a 0–70% range. When average CAC is provided, misattributed spend is divided by CAC to estimate the number of acquisitions likely credited to the wrong channel each month.
This is an estimate, not a measurement. A holdout test in your own accounts is the only way to know your real attribution error. For the full write-up, see Why your marketing dashboard is lying to you.