Cash Runway Calculator
Calculate how many months of runway your cash buys at your current monthly burn — and the approximate month your cash runs out.
How it works
Runway (months) = current cash ÷ monthly net burn
Runway is how long your cash lasts at the current rate of spending — cash on hand divided by monthly net burn. It answers the question every founder needs to keep in view: how many months until the money runs out. Runway is a snapshot at today’s burn, so anything that changes burn changes it: cutting costs stretches runway, while faster hiring or falling revenue shortens it. Because raising funding or reaching profitability both take time, a common rule of thumb is to keep at least 12–18 months of runway so you are never forced to raise or cut from a position of weakness.
Worked example
A company holding $400,000 in cash and burning $25,000 a month has 400,000 ÷ 25,000 = 16 months of runway. Starting today, that points to cash running low about 16 months out — the deadline to reach profitability or close the next round.
Frequently asked questions
How many months of runway should I keep?
A widely used guideline is 12–18 months. Fundraising can take several months, and unexpected setbacks eat into cash, so a longer buffer keeps you from having to raise or make deep cuts under pressure. Capital-intensive or slower-growing businesses often aim for more.
Does runway assume revenue stays the same?
This calculation uses your current net burn, which already reflects today’s revenue. If revenue grows, your net burn falls and real runway is longer than the simple figure; if revenue drops or costs rise, runway shortens. Recompute whenever your burn changes materially.
What is the difference between runway and burn rate?
Burn rate is how much cash you spend per month; runway is how many months that cash lasts. Runway = cash ÷ burn, so the two move together — halving your burn roughly doubles your runway from the same cash balance.
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Educational estimate, not financial advice.