How do you assess market size using TAM, SAM, and SOM? Define each.

• A. TAM is total addressable market, SAM is serviceable available market, SOM is serviceable obtainable market.
• B. TAM is serviceable obtainable market, SAM is total addressable market, SOM is serviceable available market.
• C. TAM is total addressable market, SAM is serviceable obtainable market, SOM is serviceable available market.
• D. TAM is total addressable market, SAM is serviceable available market, SOM is serviceable obtainable market.

Answer: (A)

When sizing a market for a venture, you move from the broadest possible demand to what you can realistically reach and win. TAM is the total addressable market—the entire demand for the product category if every potential customer could buy it. SAM is the serviceable available market—the portion of TAM you could actually reach with your current product, business model, and geographic reach. SOM is the serviceable obtainable market—the slice of SAM you can realistically capture in the near term given competition, capacity, and resources.

This mapping matches the standard definitions: total addressable market, serviceable available market, and serviceable obtainable market. For example, if the global demand for a new fitness tracker is $20B (TAM), and you can sell it only online in North America and Western Europe with your current lineup (SAM is $6B), and you project you can capture 20% of that reachable segment in the near term (SOM is $1.2B).