Startup Runway Calculator

Enter your cash on hand and monthly net burn — or your revenue and expenses — and instantly see how many months of runway you have and the projected date your cash hits zero.

📖 How it works & FAQ

Cash on hand ($)

How do you track burn?

Monthly net burn ($)

Runway is the number of months your startup can keep operating before the bank account hits zero. The math is deliberately simple: runway = cash on hand ÷ monthly net burn. If you have $500,000 in the bank and burn a net $40,000 a month, you have 12.5 months of runway. This calculator also converts that into a calendar date, so instead of a vague number you get a concrete deadline to plan a raise, a pivot, or a path to breakeven around. Everything runs in your browser — your financials never leave your device.

Gross burn vs. net burn

Gross burn is your total monthly spending. Net burn is what actually leaves the bank after revenue comes in: expenses minus revenue. Runway should always be calculated on net burn, which is why this tool lets you enter it directly or derive it from monthly revenue and expenses. If revenue exceeds expenses, your net burn is negative — you are “default alive,” and the calculator shows your monthly cash gain instead of a zero-cash date. Keep in mind the projection assumes a flat run rate; hiring, churn, and one-off costs will move the real date, so every input stays editable for quick what-if checks.

How to use it

Enter your current cash on hand — bank balances plus any committed funds already wired.
Choose how you track burn: type your monthly net burn directly, or switch to revenue & expenses and let the tool subtract for you.
Read the results instantly: months of runway, your approximate zero-cash date, computed net burn, and a status note.
Change any number to model scenarios — a hiring freeze, a price increase, a new lease — and watch the runway update live.

Estimates only — this tool is not professional financial, tax, or legal advice.

FAQ

How much runway should a startup have?: Common guidance is 12–18 months after a funding round. Start fundraising while you still have 6–9 months left, because a typical raise takes 3–6 months to close.
Does the calculator account for burn growing over time?: No — it assumes your current net burn stays flat. If you plan to hire, enter your average expected burn for the next six months instead of this month’s figure, and re-run it monthly.
What if my revenue is higher than my expenses?: Then your net burn is negative and runway is effectively infinite at the current run rate. The tool flags you as default alive and shows your monthly cash gain.
Is my financial data uploaded anywhere?: No. All calculations happen in your browser with plain JavaScript — nothing is sent to a server, stored, or tracked.