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TAM, SAM and SOM calculator

Top-down sizing — 'a 1% share of a $40bn market' — is the single most common reason a memo fails scrutiny. This builds the number the other way: count the buyers, narrow to the ones you can actually qualify and reach, then apply a win rate you can defend.

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Total market (TAM)

Count of every organisation or person with the problem, times what a solution is worth to them per year. Use a source you can cite — a registry, census or association membership count.

Total number of potential buyers

Annual contract value per buyer (USD)

Serviceable market (SAM)

The share that fits your product today — right segment, right geography, right regulatory regime, right budget.

Buyers your product actually fits

35%

Obtainable market (SOM)

Only what your stated channel can physically reach in the plan period, times a win rate you can support with pipeline data rather than optimism.

Reachable through your channel

40%

Win rate among those reached

6%

Plan period (years)

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<a href="https://theventureiq.com/tools/market-size-calculator">TAM, SAM and SOM calculator</a> by The VentureIQ AI

The platform builds the market sizing, risk register, red-flag checks and an investment memo with every claim traced to its evidence. Every workspace starts with 2 free analyses and the full toolset.

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TAM, SAM and SOM calculator

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