Burn Rate and Runway Calculator
Gross and net monthly burn, how many months the cash lasts at today’s burn, and when it runs out or breaks even if revenue and costs grow.
Result
Runway: 11.4 monthsEstimate
A projection from steady growth rates. Real months vary, so check it against your actual bank balance often.
- Runway at today’s burn, months
- 11.4
- Gross burn, per month
- $68,000.00
- Net burn, per month
- $37,000.00
https://calcgallery.com/business-investing/burn-rate-runway-calculator/
Results are arithmetic estimates based on the assumptions you enter, not accounting, tax, investment or lending advice. Forecasts can be wrong and important decisions should be checked with a qualified adviser. Read the full disclaimer
How to use the Burn Rate and Runway Calculator
- Enter the cash you have, what goes out of the bank in a typical month, and the revenue that comes in.
- Optionally enter monthly growth rates for revenue and expenses, to see whether revenue catches up before the cash runs out.
- Optionally add funding or a loan and the month it arrives.
The formulas
gross burn = monthly expensesnet burn = monthly expenses − monthly revenuerunway = cash ÷ net burnWith growth rates, the page steps forward one month at a time. In month n, revenue is today’s revenue × (1 + revenue growth)ⁿ and expenses are today’s expenses × (1 + expense growth)ⁿ. The gap comes out of the cash. If the cash cannot cover a full month, the runway ends partway through that month. If revenue reaches expenses first, the page reports that month instead of a runway.
Growth rates compound
A revenue growth rate of 8% a month is large: it more than doubles revenue in ten months. Small changes in these rates move the answer a lot, so try a cautious case alongside the hopeful one. The break-even month is the first month revenue covers expenses at these rates, not a promise that it will.
What the diagram shows
The cash balance month by month, from today until it reaches zero or revenue catches up.
With your numbers
- Net burn = $68,000.00 − $31,000.00 = $37,000.00 a month
- At today’s burn: $420,000.00 ÷ $37,000.00 = 11.35 months
- With growth, each month’s revenue and expenses are grown from today’s, and the gap comes out of the cash until it runs out or revenue catches up
Quick reference
A projection from steady growth rates. Real months vary, so check it against your actual bank balance often.
| Example | Runway |
|---|---|
| 420,000 cash, 37,000 net burn | 11.4 |
| Revenue +8% a month, costs +2% | |
| Costs rising 5% a month | 7.8 |
| Already profitable | |
| With 250,000 arriving in month 9 | 18.1 |
| 50,000 cash, no revenue | 6.3 |
Common questions about the Burn Rate and Runway Calculator
- What is the difference between gross and net burn?
- Gross burn is everything you spend in a month. Net burn is what you spend less what you collect, which is how fast the bank balance actually falls. Runway uses net burn. Gross burn matters when revenue is uncertain: if sales stopped, it is the rate you would burn at.
- Why do the two runways differ?
- The runway at today's burn assumes nothing changes. The modelled runway grows revenue and expenses at the rates you enter. With costs rising 5% a month and flat revenue, 420,000 lasts about 7.8 months instead of 11.4. With revenue growing faster than costs, the business may never run out.
- How much runway should I have?
- This page does not recommend a number. What is enough depends on how long it takes to raise money or cut costs in your situation, how predictable your revenue is, and what the cash is for.
- Should I include loan repayments and tax?
- Yes, if they leave the bank. Runway is about cash, not profit, so include anything you pay and leave out non-cash costs like depreciation.