Product Market Fit

Product Market Fit

Startup Playbooks

Paul Graham’s Billion-Dollar Formula

The Two Numbers Behind a Breakout Startup and a Practical Kit to Test Yours

Guillermo Flor's avatar
Guillermo Flor
Sep 25, 2026
∙ Paid

In a recent talk (and essay), Paul Graham revealed the two numbers that determine how big a startup can get:

  • how fast it grows

  • how long that growth can continue

To show what they mean, he started with a company making $10,000 a month. At 15% monthly growth, it would be making roughly $44 million a month five years later. The calculation takes seconds. The difficult question is whether a startup can keep growing long enough for the math to matter.

That depends on more than a promising chart:

  • Are users coming back and telling their friends?

  • Is there enough demand beyond your first group of customers?

  • And which of those two numbers is actually holding your company back?

📚 In this guide, we turn Graham’s argument into a practical kit. You’ll calculate your real growth rate, use the same product-market fit survey that helped Superhuman go from 22% to 58%, map the demand you can realistically reach, and bring the results together in a one-page diagnosis.

The tools you’ll get:

  • The Weekly Growth Tracker

  • The Word-of-Mouth Survey

  • The Survey Analysis Prompt

  • The Demand Runway Check

  • The Idea-Filter

Inside you will find:

  1. The Math Behind a Billion-Dollar Startup

    See how two numbers can turn $10,000 in monthly revenue into $44 million.

  2. The Growth Rate YC Actually Measures

    Find out what to track each week and how your growth compares with YC’s benchmarks.

  3. Why Word of Mouth Is the Growth That Compounds

    Measure whether users love your product enough to bring in the next ones.

  4. Why Paul Graham Tells Founders to Stop Worrying About Market Size

    Learn why a small, urgent market can be the starting point for a much bigger company.

  5. Why the Best Startup Ideas Sound Bad at First

    Spot the needs and overlooked problems that could become your strongest ideas.

  6. What Changes When Anyone Can Build in a Weekend

    See why finding out what users want now matters more than shipping a first version.

  7. The Billion-Dollar Kit: Run It on Your Startup Today

    Six tools to test your growth, word of mouth and market, then decide what to fix first.


“When I think of revenue, I think of Attio”

(Shreman Shrestha, Head of Business @ Granola)

Granola’s revenue motion runs on Attio. Here’s what that adds up to:

  • Zero missed leads and 10X faster access to customer context

  • Lead triage 83% faster

  • 5 hours saved per week with automated updates

Try Now!


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1. The Math Behind a Billion-Dollar Startup

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