TAM calculator

Calculate annual TAM, SAM and SOM from customer count, annual spend and market coverage. Change the assumptions instantly, then research the evidence behind them.

Calculate your annual market size

Use organizations or individual buyers consistently.

$

Annual revenue per buyer, not monthly spend or lifetime value.

%

The share of the defined market you can serve.

%

Your planning assumption for the share of SAM you can obtain.

TAM — annual opportunity
$24,000,000

Potential customers × annual spend per customer.

SAM — annual serviceable opportunity
$6,000,000

TAM × serviceable share.

SOM — annual obtainable scenario
$240,000

SAM × obtainable share. This is an assumption-based scenario.

Customers in the obtainable scenario
200.0

Potential customers × serviceable share × obtainable share.

What is a TAM calculator?

A TAM calculator estimates the annual revenue opportunity for a defined product and customer group. Total addressable market (TAM) represents the entire defined market; serviceable available market (SAM) limits that opportunity to customers you can serve; serviceable obtainable market (SOM) applies an attainable share of SAM.

This bottom-up model uses one annual spend assumption across the customer group. Count the same buyer only once and use annual US-dollar revenue throughout. Coverage and attainable share are planning assumptions that need evidence. SOM is a scenario, not a sales forecast or company valuation.

TAM = customers × annual spend; SAM = TAM × serviceable share; SOM = SAM × attainable share

How to use a TAM calculator

Keep customer units, currency and the annual period consistent.

  1. 01

    Define the buyer

    Count organizations or individuals buying the product. Do not mix seats with companies unless annual spend uses the same unit.

  2. 02

    Set annual spend and coverage

    Enter annual revenue per buyer and the percentage of the defined market your offer can serve.

  3. 03

    Stress-test obtainable share

    Choose a share of the serviceable market and explain the sales capacity, competition and time horizon behind it.

What can you use this research for?

Use the result to expose the assumptions behind a business decision.

  • Business planning

    Compare the same product across customer segments with explicit buyer counts and spend assumptions.

  • Pitch preparation

    Show investors how a bottom-up estimate was calculated, then attach sources for the inputs.

  • Expansion decisions

    Model a new region by changing serviceable coverage while keeping the buyer and period consistent.

How market sizing becomes customer research

Check who your buyers are before treating the calculated opportunity as a sales plan.

Ideal customer profile generator
How market sizing becomes customer research01What is a TAMcalculator?02How marketsizing becomescustomerresearch03Ideal customerprofilegenerator

Get better results with connectors

Carry your current inputs and results into a source-backed market brief.

Useful connectors

  • Google Sheets
  • Google Docs
  • Notion

Research the assumptions behind your market size

Check who your buyers are before treating the calculated opportunity as a sales plan.

Research my assumptionsBrowse workflow examples

TAM calculator FAQs

What is the difference between TAM, SAM and SOM?

TAM is the entire defined annual opportunity. SAM is the part your product and geography can serve. SOM is the share of SAM you assume you can obtain. The percentages use different denominators.

Can this calculator find the market size for me?

The on-page calculation uses the inputs you provide. You can separately ask Okou to research customer counts and spending benchmarks with sources; research uses account credits.

Is the TAM calculator free?

Yes. The calculator runs directly on this page without an account. Optional research in Okou requires sign-in and available credits.

Okou also has the ideal customer profile generator, the company research tool and the AI competitor analysis.

Research the assumptions behind your market size

Carry your current inputs and results into a source-backed market brief.

Research my assumptions