What do TAM, SAM and SOM stand for?

TAM is Total Addressable Market — every person or business that could ever buy. SAM is Serviceable Available Market — the slice you can realistically reach with your product, geography and channels. SOM is Serviceable Obtainable Market — the share of that slice you can actually win in the first few years.

How do you calculate TAM, SAM and SOM?

TAM = everyone with the problem × price per year. SAM = TAM × the percentage you can serve (your region, your segment, your channel). SOM = SAM × the market share you can realistically capture early on, usually 1–5%.

What is a good SOM for a startup?

Investors typically expect 1–5% of SAM in the early years. A SOM claim above 10% signals unrealistic assumptions unless you have strong distribution evidence.

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TAM, SAM, SOM calculator — explained in plain English

These three abbreviations intimidate most first-time founders, but they answer one simple question: "How much money could this idea actually make?" Type your numbers below and watch your market size appear — each term is explained as you go. No sign-up needed.

Your numbers

Everyone who has this problemPeople or businesses worldwide who could ever buy. This builds your TAM.

people/yr

Your price per customer, per yearWhat one customer pays you annually (subscription, or average yearly spend).

Currency

% you can actually serve (SAM)Your language, region, channel and product limits. Often 10–30% of TAM.

% you'll realistically win (SOM)Honest market share in your first years. 1–5% is credible; above 10% needs proof.

TAM

The whole ocean

$600,000,000

per year

SAM

The part you can reach

$120,000,000

per year

SOM

What you can win

$2,400,000

per year · 2.0% of SAM

What do these abbreviations actually mean?

TAM — Total Addressable Market

Imagine every single person or business in the world who has the problem you solve. If they ALL bought from you at your price, how much money would that be per year? That's your TAM. It's the biggest possible number — the whole ocean, not the part you'll actually fish.

Example: You sell a budgeting app for freelancers. There are 60 million freelancers worldwide, and your app costs $60/year. TAM = 60,000,000 × $60 = $3.6 billion per year.

SAM — Serviceable Available Market

Of that whole ocean, which part can you actually serve? Maybe your app is only in English, or only works in your country, or only suits a certain type of customer. SAM is TAM shrunk down to the people your product can genuinely reach today.

Example: Your app is only in English and you market only in the US and UK. That's about 12 million of the 60 million freelancers — 20%. SAM = $3.6B × 20% = $720 million per year.

SOM — Serviceable Obtainable Market

Now be honest: of the people you CAN reach, how many will actually buy from YOU in the next few years — given competitors, your budget and your brand being new? SOM is that realistic slice. This is the number investors scrutinise most, because it shows whether you understand reality.

Example: You estimate you can win 2% of your reachable market in 3 years. SOM = $720M × 2% = $14.4 million per year. A claim above 10% usually raises eyebrows unless you can prove distribution.

Questions people ask

Why do investors ask for TAM, SAM and SOM?: Because the three numbers show whether the prize is big enough (TAM), whether you can reach it (SAM), and whether your plan is honest (SOM). A huge TAM with an unrealistic SOM is a red flag, not a strength.
Should I calculate top-down or bottom-up?: Bottom-up (customers × price) is far more credible than quoting an industry report. This calculator uses the bottom-up method. Read the full walkthrough in our TAM, SAM, SOM guide.
What if my numbers are just guesses?: Every early estimate is a guess — the skill is making it an honest one. A full idea check sizes the reachable market for your specific idea, in your own currency, and stress-tests the assumptions behind it.

Want this done properly for your idea?

This calculator gives you the arithmetic. Samchu's nine AI experts go further: they size the reachable market for your specific idea in your currency, check the competitors already taking that share, and tell you whether your SOM assumption survives scrutiny.

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