Startup Runway Calculator

The startup runway calculator is a free tool that tells you how many months of operating capital your company has left, given your current cash balance, burn rate, and revenue. It is designed for founders, CFOs, and investors who need a quick, clear answer to "how long can we operate before we need more funding?"

Enter your current cash balance, monthly gross burn (total expenses), and monthly revenue. The calculator derives your net burn rate (expenses minus revenue) and divides it into your cash balance to give runway in months and a projected cash-out date. Scenario cards show how your runway changes if burn increases or decreases by 20%, making it easy to stress-test your plan. Adjust the revenue growth rate slider to model how organic growth extends your runway over time.

This burn rate and runway calculator is most commonly used when preparing for a fundraising round (to determine timing and urgency), running a board review, or deciding whether to make a new hire. For example, a startup with $800K in the bank, $70K monthly burn, and $15K MRR has roughly 14.5 months of net runway — enough to run a Series A process but not with much margin. If burn rises 20%, that drops to about 11 months, which changes the fundraising calculus significantly.