An investor asked me about my burn rate. I gave them the wrong number.
That’s not a hypothetical. It’s what happens when founders are running businesses without understanding the financial language investors use. Burn rate and runway aren’t just accounting terms; they are what investors use to determine whether you’re in control of your business.
Burn rate is the amount of cash your business spends each month. Total monthly expenses include everything your business spends in a month. For most founders, the more useful number is your net burn, the amount you spend after accounting for revenue, which is the number after you subtract out revenue.
Runway is the number of months your available cash can keep the business operating at your current net burn rate. Your runway is equal to the amount of money you have in the bank divided by your net monthly expenses. If you have $300K in the bank and spend $30K/month net, then your runway is 10 months.
Cash flow is the movement of cash into and out of the business over time. If you’re a new business, the cash flow forecast will show whether you have enough cash to run your business, not just on paper, but month after month.
Why These Numbers Matter Beyond Just Surviving
Most founders don’t realize that investors don’t only use these numbers to determine whether your business can sustain its growth. They use them to assess how effectively you’re allocating capital.
Low revenue growth combined with high operating expenses is a warning sign. When a founder can’t explain their net burn, it is a sign of something more serious that the founder isn’t looking at the right things. Understanding basic startup financial terms isn’t about sounding smart. It’s about showing that you are using the available funds wisely.
3 Practical Ways to Extend Your Runway
You don’t always need more investment. Sometimes you need better math.
Reduce operating expense: Review all the recurring costs. Cut spending that isn’t directly helping the business grow. from that which is not directly contributing to the business. Reducing monthly spend by $5K adds two months of runway to a $300K balance.
Increase revenue velocity, which means how quickly cash from customers actually lands in your account. Shortening payment cycles or upfront invoicing can directly improve your cash position.
Secure a bridge financing round: A bridge financing round is a smaller, faster route to extend your runway while you hit the performance targets required for a major funding round.
The bottom line
Burn rate and runway for startups are simple basics, but not knowing them in a room with investors exposes you to the risk of low investor confidence. Know your net burn. Know your runway. Prepare a 12-month cash flow forecast that lets you identify potential risks before they arrive.
That’s not about being a finance expert; it’s about running your business with confidence.
Not sure what your burn rate or runway is right now? Book a free financial strategy call — we’ll calculate it with you and show you what it means for your next raise.
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