Startup Runway Calculator

Enter your financials to instantly see how many months of runway you have, when you'll run out of cash, and how growth affects your timeline.

How to Calculate Startup Runway: The Complete Guide

Startup runway is the number of months your company can continue operating before it runs out of cash, assuming no additional funding. It is one of the most important metrics for any early-stage founder because it determines how much time you have to achieve product-market fit, hit growth milestones, or close your next fundraising round.

The basic runway formula is simple: divide your current cash balance by your monthly net burn rate. Net burn is the difference between your monthly expenses and your monthly revenue. If you have $500,000 in the bank and you burn $40,000 per month net, your runway is 12.5 months.

Why Simple Runway Calculations Are Dangerous

The problem with the simple formula is that it assumes a constant burn rate. In reality, expenses increase as you hire, revenue fluctuates month-to-month, and unexpected costs arise. A single-point runway estimate gives you false confidence.

Factors That Affect Your Runway

Revenue growth rate is the single biggest lever. Customer churn works in the opposite direction. Hiring pace is usually the largest controllable expense. Payment terms and accounts receivable also matter.

When to Start Fundraising Based on Runway

Most venture capital firms recommend starting your fundraise when you have 9 to 12 months of runway remaining. This gives you enough time to run a proper process without the desperation that comes from having only 3 months of cash left.

FounderConsole connects to your actual financial data sources and runs Monte Carlo simulations to show you probabilistic runway projections with P10/P50/P90 confidence bands.