Your real number
TAM, SAM, SOM will tell you how big a market is.
They will not tell you what revenue you can earn this year.
Four lines of arithmetic will. Change the boxes to your own business, and watch a market of millions become the revenue actually in reach this year – which is a far more useful thing to own, and the most non-dilutive capital there is.
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Your revenue, in five answers.
Guess if you have to. A rough number you have thought about beats a precise one you copied from a market report.
Not everyone with a pulse – the ones your thing is actually for.
Your price, or a year of it if they pay monthly.
About 5% for a business selling to other businesses. Higher if people buy often, lower if you are new and have to explain yourself first.
As a share of the ones who are buying. Be honest about your hours, not your ambition.
One in five is 20%. One in ten is 10%.
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1
The number that goes on the slide
$30,000,000
Everyone who could buy, times the price. It is a real figure and it is not a plan.
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2
Buying right now
500
The rest are not choosing someone else. They are not choosing at all, today.
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3
You can reach
200
The ones you can actually get in front of between now and this time next year.
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4
You win
40
Customers. People who paid you.
Your real revenue, this year
$120,000
That is of the market you would have put on the slide – and it is the revenue that actually pays you.
How many customers do you need to pay yourself?
This is the question we ask founders at Mosaic, and it is the one a market size cannot answer. Put in what you need to earn, and the arithmetic runs the other way.
Before tax. The number that makes this worth doing.
Customers needed
20
On these numbers, you get there.
Now you have something to do on Monday: a number of people to find, not a market to describe. Most of our founders discover the number is smaller than they feared, and far more specific than they expected.
Most of your market is not in the room today.
In 2021 Professor John Dawes, at the Ehrenberg-Bass Institute, put a number on it: at any given moment about 95% of business buyers are not in the market at all. Only about 5% are. It is known as the 95:5 rule. Most Mosaic founders sell to other businesses, so this is not a borrowed statistic – it is their week.
The 5% is arithmetic rather than a measurement. If a purchase is made about every five years, roughly a fifth of buyers are in the market in a given year, and about a twentieth in a given quarter. So treat it as a starting guess and then argue with it:
- Selling something genuinely new? Your share is probably lower. Nobody shops for a thing they have never heard of, so first you have to teach people they have the problem.
- Selling to people rather than businesses? Usually higher, and the cheque is usually smaller. The arithmetic still holds; the numbers move.
- Selling to big organizations? Lower, slower, and the buying happens on their timetable rather than yours – which is an argument for a spread of smaller customers while the big one makes up its mind.
- Something people buy every year? Higher again. A yearly purchase puts a fifth of your market in play at any moment, not a twentieth.
And the other 95% are not wasted. They are who you are becoming familiar to, so that when their moment arrives you are the obvious call. That is patience, and patience is something you can afford when nobody else owns your company.
Three ways to go further.
Find the right door
Four questions, and an honest answer about where you belong – even when that is somewhere other than Mosaic.
Find your program →See what a round would cost
The other side of the arithmetic: what raising money actually costs you in ownership.
What a VC round would cost you →Come and build it with us
Ten weeks, a cohort of founders, and a Village of mentors – to go and find the people your number names.
Apply for Fall 2026 →