MetricsMay 28, 2026· 6 min read

What Is Marketing Attribution? Models Explained (2026)

Marketing attribution is how you assign credit for a conversion across the touchpoints that led to it. Here are the main models — last-click, first-click, linear, time-decay, position-based and data-driven — and why platforms over-claim.

Frequently asked questions

What is the best attribution model?
There's no single best model — it depends on your sales cycle and goals. Last-click is simple but overcredits the final touch; data-driven is fairer if you have enough data. Many teams use a blended view across channels as their source of truth and use platform models as inputs.
Why do my platforms report more conversions than I actually had?
Each platform uses its own attribution and windows and often claims view-through and assisted conversions, so the same sale can be counted by several platforms at once. Comparing the total to your real, blended revenue corrects the over-count.
What is blended ROAS?
Blended ROAS is total revenue divided by total ad spend across all channels, rather than any single platform's attributed figure. It's harder to game and closer to business reality, which is why it's a reliable decision metric.

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