Startup Burn Rate and Runway Calculator
Updated September 8, 2026 · By Remote Financial Services
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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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 below zero, current monthly revenue exceeds current monthly expenses; at zero, it exactly covers them. When you add monthly revenue or expense growth, the calculator simulates your cash balance month by month, compounding each rate, until cash reaches zero or it hits a 60 month cap. Staying above zero through that cap is not a profitability finding; it only means no cash-out was modeled in that period. 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.
Does surviving the model mean the business is profitable?
No. The tool distinguishes current monthly revenue above expenses (cash-flow positive) from revenue equal to expenses (cash-flow break-even). If monthly cash flow is still negative but cash stays above zero through the 60-month simulation, it reports runway beyond the modeled horizon. If the growth assumptions reach sustained break-even before cash runs out, it labels that separately.
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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 September 8, 2026. Consult a CPA or attorney about your specific situation before acting.