Total Addressable Market (TAM)

Total Addressable Market (TAM) is the full revenue opportunity that exists for a product or service if you sold to every possible customer in the market. It answers a simple question — how big could this get? — and sets the ceiling against which a realistic sales target is measured. TAM is the broadest of the three common market-sizing layers.

The other two narrow it down. SAM (Serviceable Available Market) is the slice of TAM you can actually reach given your offering, geography, and channels. SOM (Serviceable Obtainable Market) is the share of SAM you can realistically win in a given period, after competition and capacity. Founders use these figures in business plans and investor decks; sales and marketing teams use them to set quotas and prioritize where to spend effort.

There are two common ways to estimate TAM. Top-down starts from published industry reports and works inward. Bottom-up counts actual potential customers and multiplies by what each is worth — and that count is where a lead source matters. To say “there are roughly X plumbers in these regions, and each is worth Y to us,” you first need a defensible count of those businesses.

That is where gtme.business fits a market-sizing exercise. By searching a Google Maps business category across the countries, states, and cities you serve, you can build a grounded count of how many real businesses match your target profile, exported with name, address, phone, website, rating, and review count. Each search returns up to a few hundred matching listings — a focused slice, not an exhaustive census of every business in a city — so treat the totals as a strong sample for bottom-up sizing rather than a complete registry. Export to CSV on any plan, or sync to your own database on Pro and Business. See how it works, or start free with 20 searches.