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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.

Currency
%
%
TAM
$1.00B
SAM
$100.00M
SOM
$5.00M
TAMeveryone
SAMreachable
SOMwinnable

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.

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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.

That’s the free read. Now get the customers.

Kasspian maps the two or three channels your buyers actually live in, the ones to skip so you stop spreading thin, and the one move to run this week, grounded in how real founders got their first customers. Honest read on the idea included.

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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.

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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