Burn rate & runway calculator
Divide your cash by your monthly burn to see how many months you have before the tank is empty, and when to start raising.
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Burn rate & runway
What it measures
Runway is how long a company can operate before it runs out of cash. Burn rate is the net cash it loses each month.
When to use it
The most important metric for an early-stage startup. A company that runs out of cash cannot keep operating.
Watch out for
Burn rate is rarely constant and usually rises as you hire. This calculator assumes a constant burn, so the result is likely optimistic.
Burn rate & runway
How long your cash will last.
Enough time to raise, but start preparing.12–18 months
How it works
Runway (months) = Cash in Bank / Net Monthly BurnNet burn is what actually leaves the company each month: operating costs minus any revenue coming in. Divide cash by that number and you get the survival timeline, the single number investors ask about first. The subtlety is that burn is rarely constant: hiring plans, annual contracts, and growth spend all bend the curve, so a straight-line runway is usually the optimistic case. Treat the output as a ceiling, not a promise.
Worked example
With €900,000 in the bank and €75,000 net monthly burn, runway is 12 months. Since a fundraise realistically takes 3-6 months from first deck to money in the bank, the raise needs to start around month 6, not month 10. If two new hires push burn to €90,000, runway drops to 10 months and the margin for a slow round nearly disappears. This is why the standard advice is to raise 18-24 months of runway, not 12.
Common questions
What is the difference between gross and net burn?
Gross burn is total monthly operating spend; net burn subtracts revenue. A company spending €100k and earning €40k has €100k gross burn but €60k net burn. Runway is computed on net burn, because revenue extends your life.
How much runway should a startup keep?
The common rule is to raise 18-24 months and to start the next raise with at least 6 months still in the bank. Rounds routinely take 3-6 months, and negotiating leverage evaporates when the cash-out date is visible on the horizon.
How can I extend runway?
Three levers: cut burn (headcount is usually the biggest line), grow revenue (each euro of new MRR extends the timeline), or add capital (equity, venture debt, or revenue-based financing). Cuts act immediately; revenue compounds; raising takes months. Plan in that order.
Last reviewed July 2026