Bottom-Up TAM, SAM and SOM Calculator
Organize a bottom-up market estimate using customer counts and annual spend. The calculator performs arithmetic; it does not verify demand or the underlying assumptions.
How the calculation works
TAM = all eligible customers × annual spend. SAM = the customers you can serve × annual spend. SOM = the customer base you expect to obtain by a stated horizon × annual spend. Each population must fit within the previous one.
Worked example
100,000 eligible customers, 10,000 serviceable customers, 500 obtainable customers and annual spend of 1,200 imply TAM of 120 million, SAM of 12 million and SOM annual revenue of 600,000.
Read the limits before using the result
Keep geography, buyer definition and spend scope consistent. Record where counts came from. SOM is annual revenue represented by the customer base at your horizon, not total revenue accumulated over the horizon.
SBA business planning and market research resources. See our calculation and research methodology.