Keywords · Ops · Finance · Updated 2026-07-21

What is Total Addressable Market (TAM)?

Short answer: The total revenue opportunity available if a product achieved 100% market share of everyone who could theoretically buy it.

Definition

The total revenue opportunity available if a product achieved 100% market share of everyone who could theoretically buy it.

Why it matters for growth

TAM sizing helps a founder and investors judge whether a business, even if executed perfectly, can reach a meaningful scale.

Example

A founder estimates a $2 billion TAM by multiplying the total number of small businesses in a target market by average annual spend on the category.

FAQ

What is Total Addressable Market (TAM)?
The total revenue opportunity available if a product achieved 100% market share of everyone who could theoretically buy it.
Why does Total Addressable Market (TAM) matter for growth?
TAM sizing helps a founder and investors judge whether a business, even if executed perfectly, can reach a meaningful scale.
What is an example of Total Addressable Market (TAM)?
A founder estimates a $2 billion TAM by multiplying the total number of small businesses in a target market by average annual spend on the category.
What is Total Addressable Market (TAM)? Definition and growth use · Cofounderbase