Startup Burn Rate and Runway Calculator
Updated July 10, 2026 · Reviewed by Max Berger, Co-Founder
Runway is your cash balance divided by your net burn, the amount your bank balance shrinks each month after revenue. A company with $500,000 in the bank losing $50,000 a month has 10 months of runway.
Enter your cash balance, monthly revenue, and monthly operating expenses to see your gross burn, net burn, and how many months of runway you have left. Add optional growth rates to project your cash-out month.
14.3 months of runway
At this burn you run out of cash around Month 14 (September 2027).
- Gross monthly burn
- $75,000
- Net monthly burn
- $35,000
- Runway (months)
- 14.3
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These figures are a planning estimate built on standard assumptions. For numbers based on your actual books and state, book a discovery call.
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How this calculator works
This calculator uses three core numbers. Gross burn is your total monthly operating expenses. Net burn is expenses minus revenue, the amount your cash balance drops each month. Runway is cash in the bank divided by net burn, expressed in months.
When net burn is zero or below, revenue covers your costs, so there is no cash-out date and the tool reports that you are default alive. When you add monthly revenue or expense growth, the calculator stops using a flat division and instead simulates your cash balance month by month, compounding each rate, until cash reaches zero or it hits a 60 month cap. The cash-out month is the calendar month in which the balance crosses zero, counted from today.
This is a planning model, not an accounting forecast. It assumes your inputs are steady month to month unless you set a growth rate, and it does not account for one-time expenses, financing rounds, changes in payment timing, taxes, or seasonality. Treat the runway figure as a directional estimate and pressure test it against a detailed cash flow forecast before making decisions.
Worked example
Suppose you have $500,000 in the bank, $40,000 in monthly revenue, and $75,000 in monthly operating expenses, with no growth assumed.
Gross burn is your full expense line, $75,000 per month. Net burn is $75,000 minus $40,000, which is $35,000 per month. Runway is $500,000 divided by $35,000, which is about 14.3 months.
Counting forward from July 2026, that puts your cash-out around Month 14 (September 2027). With 14 months of runway you are inside the point where most founders start their next raise, so this is the moment to either begin fundraising or find ways to lower net burn and push the cash-out date out.
Frequently asked questions
What is the difference between gross burn and net burn?
Gross burn is your total monthly operating expenses, the full amount of cash going out the door each month. Net burn is expenses minus revenue, the amount your cash balance actually falls by each month. Runway is driven by net burn, since incoming revenue offsets part of what you spend.
How many months of runway should you raise with?
A common guideline is to raise enough for 12 to 24 months of runway. That window gives you time to hit the milestones that justify the next round and to fundraise before cash gets tight, since raising typically takes several months. Aim for the longer end when the market is uncertain or your milestones are far out.
How can you extend your runway?
You extend runway by lowering net burn, which means cutting expenses, growing revenue, or both. Reducing headcount, trimming software and overhead, raising prices, and speeding up collections all lower the monthly cash drain. Even a small, sustained cut to net burn moves your cash-out date out by months.
What does default alive and default dead mean?
Default alive means that at your current growth and burn you would reach profitability before the cash runs out, so you do not strictly need to raise again. Default dead means you run out of cash first unless something changes, such as a new raise or a cut in burn. The terms come from Paul Graham and are a fast way to describe whether a startup is on a survivable path.
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Book a callThese results are estimates for planning purposes only and are not tax or legal advice. Rules, rates, and thresholds change; figures on this page are current as of July 10, 2026. Consult a CPA or attorney about your specific situation before acting.