How to Calculate Your Startup Runway
Startup runway tells you how long your business can continue operating before it runs out of available cash. Understanding your runway helps you plan ahead, control spending, and recognize when you may need to increase revenue or secure additional funding.
Whether you’re launching a new business or already operating one, knowing your runway can help you make better financial decisions before a cash shortage becomes an emergency.
What is Startup Runway?
Startup runway is an estimate of how many months your business can continue operating with the cash it currently has available.
For example, if your business has $60,000 available and spends an average of $10,000 per month, your estimated runway is six months.
Runway is an estimate, not a guarantee. Changes in expenses, revenue, hiring, or unexpected costs can cause your actual runway to change.
How Do You Calculate Startup Runway?
A basic runway calculation is:
Startup Runway = Available Cash ÷ Monthly Net Burn
Your available cash is the money your business can currently use to fund operations.
Monthly net burn is the amount your business spends each month after accounting for the revenue it brings in.
For example, if you have $75,000 available and your average monthly net burn is $12,500:
$75,000 ÷ $12,500 = 6 months of runway.
Gross Burn vs. Net Burn
Gross burn is the total amount your business spends during a period.
Net burn accounts for the revenue coming into the business. For runway calculations, net burn is generally more useful because it reflects how quickly your available cash is actually being depleted.
For example, if your business spends $15,000 per month but generates $5,000 in revenue, your monthly net burn is approximately $10,000.
Why Your Runway Can Change
Your runway is not a fixed number. It can change as your business changes.
Hiring an employee, increasing advertising, purchasing equipment, losing a customer, or experiencing seasonal changes in revenue can all affect your monthly cash flow.
For that reason, it’s useful to review your runway regularly rather than calculating it only once. A monthly review can help you spot changes early and make adjustments while you still have options.
How Can You Extend Your Runway?
If your runway is shorter than you would like, there are several ways to improve it.
You might reduce unnecessary expenses, renegotiate recurring costs, delay nonessential purchases, improve pricing, increase sales, collect outstanding payments faster, or prioritize the products and customers that generate the strongest returns.
The right approach depends on your business. The goal is not simply to spend less—it is to preserve enough cash to give the business time to reach its next milestone.
When Should You Pay Attention to Your Runway?
A shrinking runway deserves attention before it becomes a crisis.
Pay particular attention when your expenses are consistently increasing, revenue is falling short of expectations, your monthly burn is rising, or you have several months of expenses ahead without a clear plan for generating additional cash.
The earlier you identify a runway problem, the more choices you typically have. Waiting until cash is nearly exhausted can significantly limit those choices.
Calculate Your Startup Runway
Want to see how long your current cash could last? Use the ThinksmithOS Startup Runway Calculator to estimate your runway based on your available cash, revenue, and expenses.
What to Do Next
Knowing your runway gives you a clearer view of how much time your business has to reach its next financial milestone.
Review your cash position regularly, monitor your monthly burn, and update your assumptions when your revenue or expenses change. Most importantly, use your runway as a planning tool—not simply as a number to watch.
The earlier you understand your cash position, the more time you have to make thoughtful decisions.