Free tools / Market Size Calculator
Work out your TAM, SAM and SOM
Your three market-size numbers with the assumptions written next to them, so you can defend them or change them.
The full read
These numbers are only as good as the idea underneath them. Pressure-test the whole thing: market sizing from real sources, the risks that could kill it, and a 2-week test plan.
Signing in also gets you the exact places your first customers are with who to reach, a new first-customer play every week, and follow-up questions saved in your workspace.
1 free analysis a month, no card.
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.
Want proof it’s not made up? See real ideas run through this tool: the buyer, the spots, and the opener actually sent.
Questions
3 answeredWhat 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.
The guide behind this tool
How to size your market (TAM, SAM, SOM)
Size your market with TAM, SAM and SOM: total demand, the slice you can serve, and the share you can realistically win. A simple, honest method for founders.
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