Article

Bottom-Up Market Sizing for Startups

Qubit Capital Free Intermediate

This one focuses squarely on the method your short answer champions, building TAM up from real customer counts and pricing rather than slicing a giant number down. It is a good deep dive once you accept that bottom-up is the way and want the mechanics. Practical on ICP counts, adoption assumptions, and unit economics.

  • Build from your ideal customer profile count times annual value
  • Ground adoption rates and pricing in observable segments
  • Bottom-up assumptions can be tested, top-down percentages cannot
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It answers 3 questions

  1. What are TAM, SAM, and SOM and how do I actually calculate them?
  2. How do I size a market for India specifically when data is messy?
  3. Investors keep asking for a top-down TAM slide, but I built my number bottoms-up. Which do I show?

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