Definition
First-click attribution assigns 100% of the conversion credit to the first known touchpoint in the path.
Example
A prospect clicks a blog ad and later converts via email; first-click assigns full credit to the blog ad.
How to use it
- Useful for evaluating acquisition channels, but it can under-credit closers.
- Keep lookback windows consistent; first-click is sensitive to window length.
- Use it to inform top-of-funnel investment, not final ROI decisions.
Common mistakes
- Using first-click to judge retargeting performance.
- Comparing first-click results to last-click without context.
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 "First-click 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
- CPL to CAC Calculator: Convert cost per lead (CPL) into CAC using lead-to-customer rate (and compute targets).
- Break-even CVR Calculator: Compute the CVR required to break even (and hit a target) given CPM, CTR, AOV, and contribution margin.
- 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.
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.