Market Sizing Calculator (TAM / SAM / SOM)
Size a market or an expansion opportunity in seconds. Enter your potential customers, the annual value of each, and the share you can serve and win to get TAM, SAM, and SOM.
How to use this honestly
TAM is everyone who could ever buy what you sell. SAM is the slice you can actually serve once you account for geography, segment, and product fit. SOM is the slice you can realistically win in the near term against the competitors and constraints in front of you. A credible SOM you can defend matters far more than a huge TAM, because the small number is the one you will be held to.
Ground each input in real research rather than wishful percentages. Count the customers you can name or source, price the annual value from deals you have actually closed, and set your serviceable and obtainable shares from evidence about reach and win rates. If you are stress testing an expansion, the same discipline applies: read how to approach market sizing for expansion, plan the move with international market entry, and pressure test your share assumptions with competitive intelligence.
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