Free tool
Market Size Calculator
Size your market in seconds — total, serviceable, and the slice you can realistically win.
TAM, SAM and SOM turn a vague 'huge market' into three honest numbers. Enter your total market size and two percentages to see what you can actually reach.
TAM (Total Addressable Market) is everyone who could ever buy the category — the whole pie.
SAM (Serviceable Addressable Market) is the slice your product and geography can actually serve.
SOM (Serviceable Obtainable Market) is the realistic share you can win in the near term, given competition and your reach. Investors care most about a credible SOM, not a giant TAM.
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Common questions
What is TAM, SAM and SOM?
TAM is everyone who could buy the category, SAM is the slice your product and geography can serve, and SOM is the share you can realistically win near-term. Investors care most about a credible SOM, not a giant TAM.
How do I calculate market size?
Start with the total market value (TAM), multiply by the percentage your product and geography can serve (SAM), then by the share you can realistically capture (SOM). Enter those numbers above to see all three.
Is a big TAM good?
A giant TAM on its own is a red flag — it's easy to inflate. A credible, defensible SOM matters far more, both to investors and to your actual plan.