one-line definition
Attribution is the process of identifying which marketing channels, campaigns, or touchpoints led a user to convert.
formula: No single formula. Common models: last-touch (credit to final click), first-touch (credit to discovery channel), multi-touch (weighted across touchpoints).
tl;dr
For solo founders, start with last-touch attribution — it's the simplest and good enough when you have 2-3 channels. Multi-touch only matters when you're spending enough across channels that overlap becomes a real question.
Simple definition
Attribution answers the question: "Which of my marketing efforts actually caused this signup or sale?" When a customer interacts with your blog post, then sees a Twitter ad, then clicks a newsletter link and signs up, each of those touchpoints played a role. Attribution models assign credit to one or more of those touchpoints. For solo founders, getting attribution roughly right prevents you from killing a channel that is quietly doing the work or doubling down on one that just happens to be the last click.
How to calculate it
There is no single formula — attribution is a model choice. Last-touch gives 100% credit to the final interaction before conversion (simplest, default in most tools). First-touch gives 100% credit to the channel that first brought the user to your site (reveals discovery channels). Multi-touch distributes credit across all touchpoints (most accurate, hardest to set up). Practically, add UTM parameters to every outbound link: ?utm_source=twitter&utm_medium=social&utm_campaign=launch. Then check your analytics tool's conversion paths. Also add a "How did you hear about us?" dropdown on signup — this catches dark social, podcasts, and word-of-mouth that no tracking pixel sees.
Example
You run a budgeting app and have three active channels: a blog (organic), a Twitter/X account, and a small Google Ads budget. Last month you got 40 signups. Using last-touch attribution in Google Analytics, you see 22 from organic, 12 from paid, and 6 from social. You consider cutting social. But your "How did you hear about us?" survey tells a different story — 15 people said they first discovered you through a viral tweet, then came back later via Google. First-touch would credit those 15 to social. The real picture is that Twitter drives awareness and Google closes the deal. Cutting either one would hurt. This is why pairing UTM-based tracking with self-reported attribution gives you a much more honest view, especially at small scale.
Related reading
Related terms
- CAC
- Organic Traffic
- Conversion Rate
FAQ
Which attribution model should an solo founder use?+
Start with last-touch attribution. It's built into most analytics tools by default and is good enough when you have 2-3 active channels. Switch to multi-touch only when you're spending meaningfully across 4+ channels.
How do I track attribution without expensive tools?+
Use UTM parameters on every link you share (utm_source, utm_medium, utm_campaign). Add a 'How did you hear about us?' field on signup. Cross-reference both — self-reported attribution catches channels like podcasts and word-of-mouth that UTMs miss.