Startup Runway: How Long Have You Got — and How to Make It Last Longer

Runway is the most fundamental survival metric for any startup. It answers the question: if nothing changes, how many months until we run out of money? Every strategic decision — when to hire, whether to expand, when to raise again — should be anchored to this number.

The Basic Calculation

Runway (months) = Cash on hand ÷ Net burn rate per month

If you have €300,000 in the bank and burn €30,000/month net, you have 10 months of runway.

But the basic calculation ignores growth. If your revenue is growing and burn is declining, runway extends. If you're increasing headcount, runway shortens. A dynamic projection is more useful.

When to Start Fundraising

The golden rule: start fundraising when you have 9 months of runway remaining — not 3 months.

• 3 months to meet investors and refine your pitch
• 3 months for due diligence and term sheet negotiation
• 3 months of buffer for delays (common)

Founders who wait until 3 months of runway are negotiating from desperation — not strength.

Runway Scenarios

Consider planning three scenarios:

• Base case: current growth and burn continue as projected
• Conservative: growth is 30% slower than expected
• Optimistic: a major deal closes, revenue jumps

Each scenario has a different runway date. Knowing your worst-case scenario helps you identify the point at which you need to make difficult decisions — and plan ahead.

The Revenue Growth Effect

A startup with €0 revenue burning €40,000/month has 7.5 months of runway on €300,000.

• Month 1: net burn €30,000
• Month 2: net burn €18,000 (if revenue hits €22,000)
• Month 3: positive cash flow

Revenue growth is the most powerful runway extension tool.

Track and Forecast Your Runway

[👉 Use the Startup Runway Calculator](/calculators/runway-calculator)

Enter your cash balance, monthly burn, and expected revenue trajectory to see your runway in each scenario — and when you need to act.