Marketing Attribution Calculator
How conversion credit splits across touchpoints under each attribution model — and how differently the same data reads depending on which you choose.
Attribution models divide credit differently: first-touch gives everything to the first interaction, last-touch to the final one, linear splits evenly, and position-based gives 40% each to first and last with the rest shared.
How the marketing attribution calculator works
Attribution models divide credit differently: first-touch gives everything to the first interaction, last-touch to the final one, linear splits evenly, and position-based gives 40% each to first and last with the rest shared.
The point of showing them together is that they disagree, often dramatically. A channel that looks worthless on last-touch can be the largest contributor on first-touch. No model is correct; they answer different questions.
Formula: linear: 1/n per touch; position-based: 40/20/40
Worked examples
| Inputs | Touchpoints | Note |
|---|---|---|
| Four touchpoints | 4 | first- and last-touch disagree completely |
| A single touchpoint | 1 | every model agrees |
| A long path | 6 | linear spreads thin |
FAQFrequently asked questions
Which attribution model is correct?
None of them. Each answers a different question — first-touch asks what created awareness, last-touch what closed the sale.
Why does last-touch dominate reporting?
Because it is the default in most analytics tools and needs no configuration. It systematically undervalues everything upstream.
What is position-based attribution?
40% to the first touch, 40% to the last, and the remaining 20% spread across the middle. It is a compromize between the two extremes.
How do I choose?
Look at several. If a channel is valuable under every model, it is valuable. If its worth depends entirely on the model, that is the finding.
What about incrementality?
It is the better question. Attribution divides credit for conversions that happened; incrementality testing asks which would not have happened otherwize.
Where these figures come from
- Interactive Advertising Bureau — measurement guidelines — the impression and viewability definitions CPM depends on
- US Federal Trade Commission — the US advertizing regulator
Last checked: September 2026. These are standard industry definitions; where platforms disagree, the page says so.