Burn Rate and Runway Calculator

Calculate burn rate and runway

Burn rate is the speed at which a startup spends its cash reserves, and runway is how long that cash will last at the current rate. This calculator works out both. Gross burn is your total monthly expenses, while net burn subtracts any monthly revenue, giving the real monthly cash loss. Dividing the cash balance by the net burn gives the runway in months, and the tool estimates the approximate date the money runs out. If revenue exceeds expenses, the business is cash-flow positive and runway is effectively unlimited.

Net burn is the figure that matters, because revenue offsets part of the spending.

Why runway drives decisions

For early-stage companies, runway is often the single most important number, because it sets the deadline by which the business must reach profitability or raise more funding. A common guideline is to start fundraising well before runway runs low, since raising capital takes months. Monitoring burn rate also disciplines spending: cutting net burn directly extends runway and buys time.

Runway assumes the current burn rate holds, so it shifts as expenses and revenue change. Recalculate it regularly and plan around a conservative figure. All calculation happens locally in your browser.

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