How long will your startup's cash last? This startup runway calculator shows your monthly burn rate, how many months of runway you have left, and the month your cash runs out. Add your revenue growth to see if you'll reach break-even in time, or plan exactly how much to raise and when to start.
Who it's for: founders and CEOs of startups that aren't profitable yet, finance leads tracking cash, and anyone planning a seed or Series A round. It also helps small business owners who are spending savings or loan money before the business breaks even.
Why use it:
- See your cash-out date months in advance, not when it's too late.
- Find out if your growth will make you profitable before the money runs out.
- Know how much to raise and the latest date to start fundraising.
Startup Runway Calculator
See how many months of cash your startup has left, when it runs out, and how much to raise next.
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Monthly expenses include salaries, rent, software, and everything else you spend. Add a revenue growth rate to see whether you reach break-even before the cash runs out. Expenses are assumed to stay the same.
Results
RunwayMonths of cash left–
Net burn rateCash you lose this month$0
Cash runs out–
Break-evenAdd a growth rate–
For educational purposes only. Results are simple estimates based on the numbers you enter. Real cash flow changes month to month, so update your numbers often. Not financial advice.
How to Use the Startup Runway Calculator
The calculator has two tabs: one to see how long your cash will last, and one to plan your next funding round.
Your runway
- Currency: Pick the currency your numbers are in. It only changes how amounts are shown; it does not convert them.
- Cash in the bank: Enter all the cash your startup has available today.
- Monthly expenses: Enter everything you spend in a typical month, including salaries, rent, software, and marketing.
- Monthly revenue: Enter the money customers pay you in a typical month. Enter 0 if you don't have revenue yet.
- Revenue growth per month (optional): Enter your average monthly growth rate to see whether you'll reach break-even before the cash runs out.
Plan your next raise
- Cash in the bank and monthly net burn: Enter your current cash and how much you lose each month.
- Runway you want after raising: Enter how many months you want the new money to last.
- Months it takes to raise: Enter a realistic estimate of how long your fundraise will take, from first meetings to money in the bank.
Results update as you type.
How Is Startup Runway Calculated?
Net burn rate = Monthly expenses − Monthly revenue
Runway (months) = Cash in the bank ÷ Net burn rate
Cash-out date = Today + Runway
Amount to raise = (Net burn × Months of runway you want) − Cash left when the round closes
Start raising by = Cash-out date − Months it takes to raise
When you add a revenue growth rate, the calculator works month by month: revenue grows, the burn shrinks, and your runway gets longer.
Example: Your startup has $500,000 in the bank. You spend $60,000 a month and bring in $20,000 in revenue.
- Your net burn is $60,000 − $20,000 = $40,000 a month.
- With no growth, your runway is $500,000 ÷ $40,000 = 12.5 months.
- If revenue grows 5% a month, your runway stretches to about 16.8 months.
- At that pace, revenue would cover expenses in month 24, but the cash runs out first. You'd need to cut costs, grow faster, or raise money.
- If you want 24 months of runway and raising takes 6 months, you'd need to raise about $700,000 and start within about six months.
Gross Burn vs. Net Burn: What's the Difference?
| Term | What it means | Example |
|---|---|---|
| Gross burn | Everything you spend in a month, before counting revenue | $60,000 a month |
| Net burn | What you spend minus what you earn; the cash you actually lose | $60,000 − $20,000 = $40,000 |
| Runway | How many months your cash lasts at your current net burn | $500,000 ÷ $40,000 = 12.5 months |
| Break-even | The point where revenue covers all your expenses, so you stop burning cash | When revenue reaches $60,000 a month |
Runway is based on net burn, because revenue offsets part of what you spend. But watch gross burn too: if revenue suddenly drops, gross burn is what you'd have to cover.
Real Example: Are You "Default Alive"?
Y Combinator co-founder Paul Graham describes a simple test every founder should run. Assuming expenses stay the same and revenue keeps growing at its recent rate, "do they make it to profitability on the money they have left?" If yes, the startup is "default alive." If not, it's "default dead," and it will need to raise money or change course to survive (Paul Graham, October 2015).
That's exactly what the growth option in this calculator checks. If your break-even month comes before your cash runs out, you're default alive. If it comes after, like month 24 in the example above, you're default dead at your current pace.
The stakes are real. In CB Insights' March 2026 study of 431 venture-backed startups that shut down, 70% ran out of capital (CB Insights). Raising more money also takes time: the median gap between a seed round and a Series A was 1.9 years in late 2025 (Carta). A short runway leaves little room for a slow fundraise.
How to Extend Your Startup's Runway
- Cut costs that don't drive growth. Review software subscriptions, office space, and contractors first.
- Grow revenue faster. Every dollar of new revenue lowers your net burn. Our business revenue calculator shows which products bring in the most.
- Collect cash sooner. Ask for annual upfront payments or shorten payment terms with customers.
- Hire carefully. Salaries are usually a startup's biggest cost, so each new hire shortens your runway.
- Start raising early. Begin well before your cash gets low, so you're not forced to accept poor terms.
Where Can You Find Your Numbers?
- Cash in the bank: Your business bank account balances, plus any other cash accounts.
- Monthly expenses and revenue: Your profit and loss statement in your accounting software. Average the last three months for a steadier number.
- Revenue growth: Compare this month's revenue with last month's, or average your growth over the last few months.
- Funding amounts: See typical round sizes in our guide to startup funding stages.
What the Startup Runway Calculator Can and Cannot Tell You
It can show your net burn rate, how many months of cash you have left, when your cash runs out, whether you'll reach break-even in time, and how much to raise next.
It cannot:
- Predict changes in your expenses. It assumes they stay the same each month.
- Account for one-time costs, seasonal swings, or late customer payments.
- Guarantee that you can raise money, or how long it will take.
- Replace a detailed cash flow forecast or advice from an accountant.
Frequently Asked Questions
How do you calculate startup runway?
Subtract your monthly revenue from your monthly expenses to get your net burn rate. Then divide your cash in the bank by your net burn. For example, $500,000 in cash and a $40,000 monthly burn gives 12.5 months of runway.
What is a burn rate?
Burn rate is how much cash a startup loses each month. Gross burn is total monthly spending. Net burn is spending minus revenue, which is the number used to calculate runway.
How much runway should a startup have?
It depends on your stage and how long it takes to reach your next milestone or funding round. Because fundraising can take months, and Carta data shows a median of about two years between seed and Series A rounds, many founders aim to keep enough runway to avoid raising under pressure.
What does "default alive" mean?
It's a term from Paul Graham. A startup is default alive if, with its current expenses and revenue growth, it will become profitable before its cash runs out. If not, it's default dead and will need more funding or changes to survive.
When should a startup start fundraising?
Start well before your cash runs low. Work backward from your cash-out date and subtract the months a raise usually takes. The calculator's second tab shows the latest date you should start.
Final Takeaway
Runway is the most important number for any startup that isn't profitable yet. Use the startup runway calculator above to know exactly when your cash runs out, check whether you're on track to break even, and start raising money while you still have time to do it on your terms.
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