Bottom-up: TAM is the number of potential customers times what each pays per year; SAM is the share of that market your product and channels can actually serve; SOM is the share of SAM you can realistically win in the next few years. For example, 2 million potential customers at $240 a year is a $480M TAM; 25% serviceable is a $120M SAM; winning 2% of that is a $2.4M SOM.
Free TAM SAM SOM calculator. Estimate your total, serviceable and obtainable market bottom-up from the number of potential customers and your annual price.
Open TAM SAM SOM Calculator → Free toolFree SaaS valuation calculator. Estimate what a SaaS business is worth from its MRR or ARR and a revenue multiple, see a low to high range, and check the multiple behind any offer.
Open SaaS Valuation Calculator →Taking a percentage of a large industry figure is easy but hard to defend. Counting customers and multiplying by a real price uses inputs anyone can check, which investors and you can reason about.
SAM should reflect real limits such as the regions, languages, platforms and customer types you serve. SOM should be justified by your channels and conversion rates; for a new product it is usually a small share.
TAM is everyone who could buy this kind of product; SAM is the part your product and channels can reach.
It is a reasoned target for the share you can win, not a guarantee.
Annual is the convention for market size, so multiply monthly prices by 12.