Essay · about 1,200 words

Ways to Think About Market Size

Benedict Evans Free Intermediate

This is the sharpest short essay on why a naive market number lies to you. Evans shows that a new product can either shrink a market (cheaper, lower revenue per user) or explode it (many more users, new uses), so copying an existing industry's revenue is not your TAM. Read it before you write a single number, because it reframes TAM as a judgment about who buys and why, not a spreadsheet.

  • A better, cheaper product changes the market, so today's industry size is only a proxy
  • Ask who buys now and who buys once it is good enough and affordable
  • Numbers are a starting point for judgment, not a substitute for it
Open on ben-evans.com ↗

The question it answers

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

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