You Know What's In Your Bank Account. But Do You Know How Long It Will Last?

Every product founder I've ever worked with checks their bank balance first thing in the morning. Before coffee in some cases. It's practically a reflex — the instinctive daily pulse-check that tells you whether today is going to feel okay or not.

And that habit makes complete sense. When you're running a physical product business, cash is oxygen.

But here's the thing: knowing what you have right now is not the same as knowing how long it lasts. Or where it's quietly going.

There's a term for this in startup finance: runway. It's simply how many months your business can keep operating at its current spending rate before the money runs out. It sounds basic. Most founders assume they have a feel for it. But in my experience, very few can actually tell you the number — not because they're bad at business, but because nobody ever told them to calculate it, and the daily bank balance check feels like enough.

It isn't.

Nearly 4 in 10 small businesses have less than one month's worth of operating expenses on hand. One month. That's not a runway — that's a very short hallway.

29% of small businesses fail because they simply run out of cash. Not because the product wasn't good. Not because customers didn't want it. Because the money ran out before anyone saw it coming.

The difference between a balance and a runway

Your bank balance tells you where you are today. Your runway tells you where you're headed and how much time you have to change course if needed.

Think of it this way: a pilot who only looks at the fuel gauge without knowing the distance to the next airport isn't flying — they're hoping.

Calculating your runway doesn't require a finance degree. At its simplest: take your current cash on hand, divide it by what you bring in each month on average less what you spend each month on average, and that's how many months you have. If your burn rate varies significantly, use a three-month average for accuracy.

But here's where it gets more useful than just a number. Once you know your runway, you can start to see why it is what it is. Where is the cash actually going each month? Which expenses are fixed and which are variable? What happens to that number if you have a slow month? What happens if you have a great one?

Founders who track runway closely can course-correct early, extend operating time, and redirect capital toward growth-driving priorities. That's not just financial housekeeping — that's the difference between a business that reacts to crises and one that sees them coming.

Resilience is a number

Resilience isn't a mindset. It's a number. And then it's the decisions you make because you know that number.

So — how many months do you have?