Definition
Attribution is the method used to assign credit for conversions to channels, campaigns, and touchpoints.
Example
In last-click attribution, 100% of credit goes to the final touchpoint. In multi-touch attribution, credit is split across touchpoints.
How to use it
- Define attribution consistently before comparing ROAS/CPA across channels.
- Use incrementality tests when possible to estimate true lift.
Common mistakes
- Treating attribution as causal truth (it's model-based credit).
- Comparing channels with different windows and tracking coverage as if the numbers are comparable.
Why this matters
This term matters because it affects how you interpret performance and make budget decisions. If you use inconsistent definitions or windows, ROAS/CPA can look "better" while profit gets worse.
Practical checklist
- Write a 1-line definition for "Attribution" that your team will use consistently.
- Keep the time window consistent (weekly/monthly/quarterly) when comparing trends.
- Segment results (channel/plan/cohort) before drawing big conclusions from blended averages.
- Sanity-check with a related calculator from the same category on MetricKit.
- Read the related guide (e.g., Attribution vs incrementality: what to trust, when, and how to test) for context and common pitfalls.
Where to use this on MetricKit
Calculators
- Click-through Conversion Rate Calculator: Calculate click-through conversion rate (click-to-conversion CVR) and estimate required clicks for target conversions.
- ROAS Calculator: Calculate Return on Ad Spend (ROAS) and estimate contribution profit after ad spend.
- Break-even ROAS Calculator: Estimate the break-even ROAS based on contribution margin assumptions.
- Target ROAS Calculator: Estimate a target ROAS to cover variable costs plus a desired margin buffer.
- Paid Ads Funnel Calculator: Model CPM -> CTR -> CVR to estimate CPC, CPA, ROAS, and profit per 1,000 impressions (with margin and variable costs).
Guides
- Attribution vs incrementality: what to trust, when, and how to test: A practical guide to attribution vs incrementality: common attribution models, window pitfalls, how MER/marginal ROAS fit in, and how to run holdout/geo tests.
- UTM + GA4 attribution: practical tracking for paid ads (without lying to yourself): A practical guide to UTMs and GA4: consistent source/medium/campaign tagging, conversion deduplication, and common attribution traps.