Template

Top-Down Market Sizing: Step-by-Step TAM, SAM, SOM (with Examples and Template)

Data-Mania Free Intermediate

Even though your primary build should be bottom-up, you still want a top-down triangulation to check it, and this gives you a step-by-step method plus a template for that. It is honest that top-down is a sanity check, not the headline, and shows worked examples. Use it as the second number you compare against your bottom-up build.

  • Top-down is a cross-check, not your primary number
  • When top-down and bottom-up roughly agree, the number is stronger
  • Includes a template and worked examples to follow
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The question it answers

  1. What are TAM, SAM, and SOM and how do I actually calculate them?

Read with it

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  4. When there is no category report to point at, you have to build the number yourself, and this is the essay that teaches you... Andreessen Horowitz Essay · ~20 min read 16 More Startup Metrics Anu Hariharan, Frank Chen, Jeff Jordan
  5. A concrete, copyable Google Sheet (no paywall, no credit card) that builds your number bottoms-up from customer segments and... Visible.vc Template · ~15 min to fill in Total Addressable Market Template (free Google Sheet) Mike Preuss
  6. This lays out both the top-down (start from a big industry number) and bottom-up (build up from your own price times likely... HubSpot Blog Article · ~12 min read TAM, SAM & SOM: What Do They Mean & How Do You Calculate Them? Clifford Chi
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