Skip to content
=CalculateMyStuff

Runway Calculator

Project how long your startup can operate with its current cash, burn rate, and revenue growth.

$

Total cash available in the bank

$

Total monthly operating expenses

$

Current monthly revenue

%

Monthly revenue growth rate

Enter your cash and burn details, then click Calculate.

How Runway Calculation Works

What is Runway?

Runway tells you how long your startup can survive with its current cash and spending patterns. It is the most fundamental survival metric for any venture-backed company. Without enough runway, you cannot execute your strategy, and you lose negotiating leverage with investors.

Simple Runway Calculation

The basic formula is straightforward: Runway = Cash Balance / Monthly Net Burn. If you have $1.5M in the bank and spend $100K more than you earn each month, you have 15 months of runway. This simple calculation assumes flat revenue and expenses.

Modeling Revenue Growth

In practice, most startups have growing revenue. This calculator lets you model monthly revenue growth to get a more accurate projection. With a 10% monthly growth rate, a startup earning $20K/month would earn $22K next month, $24.2K the month after, and so on. This compounding effect can significantly extend your runway.

Month-by-Month Projection

Rather than a single number, this calculator shows you a month-by-month cash projection. You can see exactly when cash runs out, how revenue growth bends the curve, and at what point you might reach breakeven. This detailed view helps you plan fundraising timing and expense management.

Default Alive vs Default Dead

Paul Graham coined these terms: if your current trajectory leads to profitability before cash runs out, you are "default alive." If not, you are "default dead." Knowing which category you fall into changes how you should operate and how urgently you need to fundraise.

Frequently asked questions

Runway is the number of months a startup can continue operating before running out of cash. It is calculated by dividing your current cash balance by your monthly net burn rate (expenses minus revenue). Runway is one of the most critical metrics for any startup, as it determines your timeline for reaching profitability or raising the next round of funding.

Most advisors recommend starting your fundraise when you have 6 to 9 months of runway remaining. Fundraising typically takes 3 to 6 months, so starting early gives you a buffer. Ideally, each funding round should provide 18 to 24 months of runway, giving you enough time to hit milestones that justify a higher valuation for the next round.

You can extend runway by reducing expenses (cutting non-essential costs, renegotiating contracts, slowing hiring) or increasing revenue (raising prices, improving conversion, upselling existing customers). Other strategies include bridge financing, revenue-based financing, or government grants. Extending runway buys you more time to find product-market fit.

Revenue growth can dramatically extend your runway. If your revenue is growing month over month, each successive month your net burn decreases. With strong enough growth, you may reach profitability before running out of cash (sometimes called being "default alive"). This calculator models revenue growth to give you a more realistic projection.

Related calculators