TAM SAM SOM Calculator: Size Your Market
Enter how many customers you could serve, how much each is worth and how much of the market you can realistically win. See your TAM, SAM and SOM instantly, then download the free Excel version.
How the TAM SAM SOM calculator works
TAM (total addressable market) is the revenue available if every possible customer bought from you. SAM (serviceable addressable market) is the part you can actually reach with your product, location and sales channels. SOM (serviceable obtainable market) is the share of SAM you can realistically win in the first few years.
The formulas
Free Excel version with a top-down cross-check
Download the Excel templateFrequently asked questions
What is the difference between TAM, SAM and SOM?
TAM is the total revenue available if everyone who could buy did buy. SAM is the part of TAM you can actually serve with your product, location and channels. SOM is the share of SAM you can realistically win in the near term.
What is a good SOM as a share of TAM?
It is usually a small number, often well under 5% of TAM. If your SOM looks like a large share of the whole market, your share or reach assumption is probably too high.
Should I use top-down or bottom-up market sizing?
Use both. Bottom-up (customers x price) is easier to defend. Top-down (an industry report x your segment share) is a cross-check. If the two SAM figures are within roughly 20-30% of each other, the estimate is reasonable.
Where can I find the number of target businesses?
Public sources such as the US Census Bureau County Business Patterns and Nonemployer Statistics, and BLS data, list business counts by industry and size.
Is this calculator financial advice?
No. It is an educational estimate that depends entirely on the numbers you enter.
Need market research or a custom model built for you?
See our research servicesMore free tools: Free Excel templates · Break-even calculator · All free calculators
Estimates only. Results depend on the numbers you enter and are not financial, tax or legal advice.