TAM vs SAM vs SOM: A Plain‑English Playbook for Founders
Step by step, turn Total Addressable Market into realistic Serviceable and Obtainable numbers with Olympus Intel’s Model Builder—no spreadsheets required.
TAM vs SAM vs SOM: The Plain‑English Playbook for Founders
You don’t need an MBA—or a mountain of spreadsheets—to turn Total Addressable Market into the more practical Serviceable and Obtainable numbers investors actually care about. This guide walks you through the exact steps inside Olympus Intel Model Builder, so you can size, refine, and defend your market opportunity in minutes.
Open Model Builder and start by defining your market segments. Olympus Intel gives you three paths:
AI Segment Generator – paste your 2‑line elevator pitch; the platform proposes matching NAICS codes.
Pre‑defined segment library – multi‑select common industries (helpful if you already know your verticals).
Custom picker with company look‑up – search “Apple” or “3M” to inherit their primary NAICS codes.
After choosing segments, enter (or import) your revenue model—one‑off, subscription, usage‑based, or a mix. Model Builder instantly multiplies those SKUs across every establishment in each segment to calculate TAM.
One click turns raw census data into a TAM chart you can paste into any deck.
Step 2 – Narrow to SAM with constraints
TAM is inspiring—but rarely actionable. Click Next and apply constraints to reflect where you could sell once regulatory, product, or scale milestones fall into place.
Market‑segment filters – exclude industries you’ll never serve.
Geography filters – limit by state or county (handy for compliance‑heavy products).
Company‑size filters – focus on SMB, mid‑market, or enterprise tiers.
Custom constraints – drop in win‑rate assumptions, minimum ad‑spend, or other ICP traits.
This recalculates SAM instantly. If you want to see how different scenarios change the size, test them in the Market Opportunity Simulator.
Step 3 – Reality‑check SOM (Service Obtainable)
SOM asks, “Given our current headcount and budget, what can we win this year?” Adjust the same filters—especially win rate and sales‑team coverage—to derive a sober, defensible SOM. This number is gold for operational planning and board updates.
Pro tip: Investors love seeing SOM sit at 5–15 % of TAM. It signals ambition and realism. See our SOM deep dive for typical ratios by industry.
Need automated takeaways? Activate AI‑Powered Market Insights to generate a narrative of the gaps between TAM, SAM, and SOM—perfect for slide notes.
Investor Q&A cheat‑sheet
Common question
How to answer with Olympus Intel
“Why is your SOM only 8 % of TAM?”
Show the Constraints tab—highlight geography & current headcount limits. Explain hiring plan to unlock additional SAM down the road.
“Which segment drives most of your SAM?”
Display the SAM-by‑segment table export (CSV) and note the % split. Link opportunity back to your B2B ICP.
“How sensitive is TAM to price?”
Re‑run the Market Opportunity Simulator with ±10 % pricing; share delta. Mention pricing analysis use case.
“What data sources back these numbers?”
Point to Olympus Intel’s U.S. Census datasets (Economic Census & County Business Patterns). For a primer, link to Which datasets should I use?.
A step-by-step guide to bottoms-up market sizing for entrepreneurs. Learn to calculate TAM, SAM, and SOM with real data to make informed decisions.
Tyler Sinclair
Jun 5, 2025
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