What is Total Addressable Market (TAM)?
Total Addressable Market is the total revenue opportunity available for a product or service if it achieved 100% market share.
Total Addressable Market is the total revenue opportunity available for a product or service if it achieved 100% market share. TAM is used by investors and strategists to evaluate the scale of opportunity.
TAM can be calculated top-down (use industry research: "The global SaaS market is $200B, our segment is 5% = $10B TAM") or bottom-up (count potential customers × average revenue per customer).
TAM, SAM, SOM: TAM (total market), SAM (Serviceable Addressable Market — the portion you can reach), SOM (Serviceable Obtainable Market — what you can realistically capture in 3-5 years). Investors care most about SAM and your path to capturing SOM.
VCs typically want TAM of $1B+ for venture-scale investments. Smaller TAMs can support great businesses but aren't suitable for the venture model (which requires 10-100x returns).
Why It Matters
TAM determines whether a business opportunity is "venture-scale." It shapes strategy, fundraising, and exit expectations. Overestimating TAM leads to bad strategy; underestimating it limits ambition.
Frequently Asked Questions
What is TAM?
Total Addressable Market — the total revenue opportunity if you achieved 100% market share. Used by investors to evaluate the scale of the business opportunity.
How do you calculate TAM?
Top-down: industry research and segmentation. Bottom-up: potential customers × average revenue per customer. Bottom-up is more credible for fundraising.
Related Terms
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