Free calculator
How much runway do you have left?
Enter your cash, monthly costs and revenue. See the month your money runs out, when to start fundraising, and whether growth gets you to profit first.
Your numbers
Everything you can spend today.
Salaries, tools, hosting, ads. All of it.
Cash coming in per month, today.
Runs in your browser. Nothing you type is sent or stored.
Runway
Default alive5+ years
Your cash outlasts the 5-year projection. At this growth you reach profit before the money runs out.
- Net burn this month
- $20,000
- Runway without growth
- 12 months
- Break-even
- Jan 2028
- Start raising by
- Not needed
Cash in the bank
You reach break-even in January 2028, with $48,922 still in the bank at the low point.
Quick answer
How do you calculate startup runway?
Runway = cash in the bank ÷ monthly net burn, where net burn is monthly expenses minus monthly revenue. $250,000 in the bank with $30,000 of costs and $10,000 of revenue is $20,000 of net burn, so 12.5 months of runway. If revenue grows faster than costs, the real runway is longer, and at high enough growth the cash never runs out: that is "default alive".
How to use the runway calculator
- Enter your cash
Type the cash you can spend today: bank balances, minus anything already committed.
- Enter monthly expenses and revenue
Use last month’s real numbers, or an average of the last three months if they move around.
- Set the growth rates
Move the sliders to your monthly revenue growth and the rate your costs rise. Leave expense growth at 0% if you plan no new hires.
- Read the result
See your runway in months, the month the cash runs out, your break-even month, and when to start raising. Copy the link to share the numbers with a cofounder or investor.
How the calculator works
Each month we add that month’s revenue to your cash and take away that month’s expenses. Then revenue and expenses each grow by the rate you set. The first month your cash drops below zero is your runway.
Net burn is expenses minus revenue. Runway without growth is cash divided by net burn: the number most founders quote, and usually the wrong one, because revenue and costs both move.
Default alive is Paul Graham’s test: at your current growth, do you reach profit on the money you already have? If yes, fundraising is a choice. If no, it is a deadline.
cash(month + 1) = cash(month) + revenue × (1 + g)ᵐ − expenses × (1 + e)ᵐHow many months of runway should a startup have?
Most investors want to see 18 to 24 months of runway after a round closes. That covers about a year of building and the three to six months the next raise takes. Under 12 months, you start fundraising from a weak position. Under 6 months, you should be cutting costs or raising now.
Three ways to extend your runway
Cut the biggest recurring costs first: unused seats, oversized cloud plans and paid ads that do not convert. Next, collect cash earlier with annual plans, since one discounted annual payment is a year of revenue today. Then grow revenue at low cost. Directory listings and launch platforms send early users without an ad budget, which is the cheapest growth most startups have.
Why growth changes everything
A startup with $200k, $30k of costs and $10k of revenue has 10 months of runway on paper. At 10% revenue growth a month it never runs out, because revenue passes costs in month 12. Small changes to the growth rate move the date further than almost any cost cut. Move the growth slider to see it.
Runway questions
- What is startup runway?
- Runway is how many months a company can keep operating before it runs out of cash, at its current spending and revenue. It is the single number that tells you how long you have to reach profit or raise money.
- How do you calculate runway?
- The simple version is cash in the bank divided by monthly net burn (expenses minus revenue). This calculator goes further: it projects revenue and expenses month by month with the growth rates you set, so the runway reflects where your numbers are heading.
- What is the difference between burn rate and net burn?
- Gross burn is everything you spend in a month. Net burn is what you spend minus what you earn. Runway depends on net burn, because revenue offsets part of your costs.
- What does default alive mean?
- Paul Graham coined it: a startup is default alive if, at its current growth and spending, it reaches profitability before the money runs out. If not, it is default dead and depends on raising more money.
- When should I start fundraising?
- Start about six months before your cash runs out. A round usually takes three to six months from first meeting to money in the bank, and you want a margin for delays.
- Is my data stored?
- No. The calculator runs entirely in your browser. Nothing you enter is sent to our servers. The share link puts your numbers in the URL, so only people you send it to see them.