/frameworks
Frameworks YC Founders Actually Use.
The handful of frameworks that show up in every YC office hour. Each one is short, opinionated, and immediately usable.
- The 40% Rule (Sean Ellis PMF Test)
Survey users: 'How would you feel if you could no longer use this product?' If 40%+ say 'very disappointed,' you have PMF.
Origin: Sean Ellis, ex-Dropbox/LogMeIn growth lead. Adopted as the de facto YC PMF benchmark.
- The Mom Test (Customer Discovery)
Ask about your user's life, not your idea. Even your mom can't lie if you ask the right questions.
Origin: Rob Fitzpatrick. Recommended in every YC office hour about user research.
- Reading the YC RFS Like an Investor
Don't pick an RFS category and 'come up with an idea.' Read the RFS to understand the partner's thesis, then bring your own evidence.
Origin: Pattern observed across YC partner office hours.
- Default Alive Calculator
Simple monthly model: revenue × (1+growth)^n vs burn × n. The crossover date is your default-alive deadline.
Origin: Paul Graham, 2015 essay. Built into every YC office hour fundraising conversation.
- The Weekly KPI Update
One number, one chart, one paragraph, sent to your investors every Monday. The discipline is the point.
Origin: Sam Altman, recurring advice in How to Start a Startup.