Monte Carlo Runway Simulator
Run thousands of simulations to see your full range of runway outcomes -- not just a single guess, but the probability distribution.
Cash Position
Simulations
Monthly Revenue
Monthly Expenses
Revenue Growth Rate
How it works
Monte Carlo simulation is a technique born in nuclear physics labs and perfected on Wall Street. Instead of plugging in one set of assumptions and getting one answer, it runs your scenario thousands of times, each time randomly varying the inputs within ranges you specify. The result is not a single number but a probability distribution -- showing you the full range of what could happen and how likely each outcome is. Named after the famous casino in Monaco, the method embraces randomness rather than pretending it does not exist.
The formula
Why it matters for your business
Single-point runway estimates give false precision. You do not have 8.3 months of runway -- you have somewhere between 5 and 14 months depending on how things go. Monte Carlo gives you that range and lets you make decisions based on probability, not hope.
Pro tip
Focus on the P25 outcome (25th percentile), not the median. If your P25 runway is less than your fundraising timeline, you need to either cut costs or start raising earlier. The median feels comfortable but half the scenarios are worse than that.
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