How do I calculate marketing ROI?

The formula: (revenue attributable to marketing − marketing cost) ÷ marketing cost. Spend $1,000, generate $4,000 in attributable revenue, and ROI is 3.0. Or 300%. The formula is trivial; the word 'attributable' is where every real difficulty lives.

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The formula: (revenue attributable to marketing − marketing cost) ÷ marketing cost. Spend $1,000, generate $4,000 in attributable revenue, and ROI is 3.0. Or 300%. The formula is trivial; the word 'attributable' is where every real difficulty lives.

For a service business, make it honest with gross margin: a $4,000 job at 50% margin returned $2,000 of contribution, not $4,000. ROI on margin is the number that decides whether marketing is making you money or just making you busy.

Attribution at small scale should be simple and consistent: pick first-touch or last-touch, tag every link, ask every new customer how they found you, and accept directional truth. Perfect attribution is a big-company sport; consistent imperfect attribution beats sporadic precision every time.

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Gross MarginRevenue minus direct costs of delivering the work, as a percentage. The profit pool all ma…AttributionDeciding which marketing touch gets credit for a sale. First click, last click, or split a…UTM Conventions That Survive Real LifeThe mental model behind source/medium/campaign, the three rules that do all the work, and …

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Everything here is free to use yourself. That’s the point. If you’d rather a senior marketer just handle it, in your accounts and your name: 20-minute call, no pitch deck.

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