⏳ Counting Down: How to Calculate and Master Your Startup’s Runway

If cash is the oxygen of a business, runway is the timer on how much air you have left.

Whether you’re a bootstrapped indie hacker or a venture-backed founder scaling up, knowing your exact runway is non-negotiable. It tells you precisely how many months your business can survive before it hits zero cash, guiding critical decisions on hiring, fundraising, and spending.

Let’s break down how to calculate your runway accurately, look at a practical example, and explore ways to stretch every dollar.

1. The Core Formula

At its heart, calculating runway is a straightforward math problem. The basic formula is:

$$text{Runway (in months)} = frac{text{Total Cash Balance}}{text{Net Burn Rate}}$$

To solve this equation, you need to define two key variables:

• Total Cash Balance: All the liquid capital you have right now across your business checking accounts, savings, and easily accessible short-term investments.
• Net Burn Rate: How much more money leaves your bank account than enters it each month.

2. Step-by-Step: How to Find Your Numbers

Step 1: Add up your liquid cash

Look at your bank feeds today. Sum up every dollar that is immediately accessible to pay bills and payroll. Do not include accounts receivable (money people owe you) unless you are certain it will clear this week.

Step 2: Calculate your average monthly expenses

Review your profit and loss (P&L) statement from the past 3 to 6 months. Add up all outgoing cash: payroll, software subscriptions, rent, marketing, taxes, and contractor fees.

Step 3: Calculate your average monthly revenue

Look at the same 3-to-6-month window and find your average monthly cash inflows.

Step 4: Determine your Net Burn Rate

Subtract your average monthly revenue from your average monthly expenses:
$$text{Net Burn} = text{Monthly Expenses} – text{Monthly Revenue}$$

Note: If your revenue is higher than your expenses, congratulations! You have a negative burn rate, meaning you are profitable and technically have an infinite runway. For everyone else, keep reading.

3. Putting It Into Practice: A Real-World Example

Imagine you run a growing SaaS startup. Here is a snapshot of your financial health over the last quarter: