Enter your cash in bank, monthly revenue and monthly expenses to see your monthly burn rate, how many months of runway you have left, and when to start fundraising. It’s free and instant, and there’s no sign-up.
What is startup runway?
Runway is the number of months your startup can keep operating before it runs out of cash, assuming your revenue and spending stay the same. It is one of the first numbers investors ask about, and the number founders should check most often.
How to calculate runway
Runway is your cash in bank divided by your monthly net burn. Net burn is what you spend each month minus what you earn:
- Net burn = monthly expenses − monthly revenue
- Runway (months) = cash in bank ÷ net burn
Example: a startup with $250,000 in the bank, $10,000 in monthly revenue and $40,000 in monthly expenses has a net burn of $30,000. Its runway is $250,000 ÷ $30,000 = 8.3 months.
Gross burn vs net burn: gross burn is your total monthly spending ($40,000 in the example). Net burn subtracts revenue ($30,000). Runway uses net burn, because revenue offsets part of what you spend.
How much runway do you need?
- Less than 6 months (red zone): cut costs or start raising now. Most rounds take longer than 6 months to close.
- 6 to 12 months (amber): start fundraising now, while you can still negotiate from strength.
- 12 to 18 months (healthy): use the time to hit the milestones that make your next round easier.
- More than 18 months (strong): you have room to invest in growth. Review your burn every quarter.
A common rule of thumb is to raise enough to give you 18 to 24 months of runway after each round.
When should you start fundraising?
The calculator assumes a funding round takes about 6 months from first meeting to money in the bank, so it subtracts 6 months from your runway. If the result is zero or negative, you should already be raising. Starting early gives you time to choose investors rather than accept the first offer.
6 ways to extend your runway
- Cancel or pause tools and subscriptions you haven’t used in the last 30 days.
- Renegotiate your biggest fixed costs, such as rent, hosting and contractors.
- Collect cash faster with upfront or annual billing.
- Slow down hiring until revenue per employee improves.
- Focus marketing spend on the one channel that brings most of your revenue.
- Recheck your runway every month, so changes never take you by surprise.
Frequently asked questions
What is a good runway for a startup?
Most advisers recommend 18 to 24 months of runway after a funding round. If you have less than 12 months, start planning your next raise or cut costs now.
What is the difference between burn rate and net burn?
Burn rate (gross burn) is everything you spend in a month. Net burn is your spending minus your revenue. Runway is calculated with net burn.
When should I start fundraising?
Start when you have at least 6 months of runway left, and ideally 9 to 12. Rounds often take 6 months or more to close.
What if my revenue is higher than my expenses?
Then your net burn is zero or negative, so your cash is not running out. The calculator shows a message instead of a runway number.
Are my numbers saved?
The calculation runs in your browser as you type. Your numbers are only stored if you choose to email yourself the results.