B2B SaaS Fundamentals
What is Total Addressable Market (TAM)?
Total Addressable Market (TAM) is the total revenue opportunity available for a product or service if a company captured 100% of its potential market, used to size opportunity and guide strategic planning.
Who Is It For?
TAM is typically calculated by leadership or product marketing, often for fundraising, planning, or strategic prioritization.
How Is It Used?
It’s used to size the overall opportunity for a product, informing decisions about market expansion, fundraising, and long-term strategy.
- Calculate TAM using top-down (industry data) or bottom-up (unit economics) methods
- Break TAM down further into SAM (serviceable available market) and SOM (serviceable obtainable market)
- Use TAM to inform fundraising narratives and long-term strategic planning
- Revisit TAM calculations as the product or target market expands
Related Terms & Concepts
Frequently Asked Questions
What’s the difference between TAM, SAM, and SOM?
TAM is the total market opportunity; SAM (serviceable available market) is the portion reachable given the product and business model; SOM (serviceable obtainable market) is the realistic share a company can capture.
Why do investors care about TAM?
A larger TAM signals more room for growth, which matters for assessing whether a company can scale into a large enough business to justify investment.
