What is TAM, SAM, and SOM?

What is TAM, SAM, and SOM is mainly about separating total demand, serviceable demand, and realistically obtainable demand. A reliable approach is to calculate TAM from all relevant spending, SAM from the segments and geographies your offer can serve, and SOM from competitive and operational constraints. For example, a global software category may have a large TAM, while a localized solution has a smaller SAM and an even smaller initial SOM. The main caution is that SOM should not be presented as an arbitrary percentage of a large market report. The final output should provide transparent opportunity layers linked to customer access, pricing, competition, sales capacity, and a realistic go-to-market plan.