#startup

The simple runway formula (cash ÷ burn) gives an optimistic answer because both inputs change. We modeled the typical 12-month evolution: hires you'll add, infrastructure that scales with users, the legal bills you didn't budget. The 20-month headline becomes 11-12 in real conditions.

Runway = cash ÷ net burn. Easy to compute, easy to get wrong because both inputs change. The non-obvious correction: start fundraising when you have 9 months left, not 4. Here's why.