Cash runway is the single most important number for an early-stage company. It answers the question every founder, investor, and employee quietly asks: how long can we keep going before we run out of money? This runway calculator takes your current cash balance, monthly expenses, and monthly revenue, then tells you exactly how many months you have left, how much more cash you need to reach your next milestone, and the funding gap you have to close.
Drag the sliders and every figure updates instantly. Whether you are raising a pre-seed round, planning a down round, or stress-testing a hiring spree, knowing your runway in advance is what lets you make decisions from strength instead of panic.
How to Use
- Enter your Cash on Hand — the total of cash, savings, and short-term investments currently sitting in the company bank account. Do not include assets you cannot spend within a month or two.
- Set your Monthly Expenses — your gross monthly operating spend: salaries and payroll taxes, rent, software subscriptions, marketing, contractors, and any other recurring outflow. Use the trailing three-to-six month average so one-off months do not skew the result.
- Enter your Monthly Revenue. If you are pre-revenue, leave this at 0. Even small early revenue dramatically stretches runway, because the model works off net burn, not gross burn.
- Set Months to Next Milestone — the time until your next funding round, major product launch, or projected profitability. This turns a static runway number into a fundraising target.
The result card shows your Net Monthly Burn, your Cash Runway in months, the Cash Needed to Reach Milestone, and the Funding Gap. If the funding gap is negative, you already hold more cash than your plan requires.
The Runway Formula
Startup runway uses the standard venture-finance identity taught in accelerator programs and used by Y Combinator, a16z, and every institutional investor doing due diligence:
Net Monthly Burn = Total Monthly Expenses − Total Monthly Revenue
Runway (months) = Cash on Hand ÷ Net Monthly Burn
Cash Needed to Reach Milestone = Net Monthly Burn × Months to Milestone
The distinction between gross burn and net burn is where most founders go wrong. Gross burn is the full amount you spend each month. Net burn subtracts whatever revenue you already bring in. If you spend $80,000 per month but collect $20,000 in recurring revenue, your net burn is $60,000 — and that $20,000 of revenue stretches your runway by a third. A company with $500,000 in the bank and $60,000 of net burn has 8.3 months of runway, not the 6.25 months someone would wrongly compute using gross spend.
If net burn drops to zero or below — meaning revenue meets or exceeds expenses — runway is effectively unlimited. That is the definition of reaching profitability, and it is the milestone most founders plan toward.
Gross vs. Net Burn: Why the Difference Matters
Imagine two startups spending $80,000 a month. Company A has no revenue, so its net burn is $80,000. Company B has $30,000 of MRR, so its net burn is only $50,000. With identical $500,000 balances:
- Company A survives 6.25 months.
- Company B survives 10 months.
Same bank balance, same headcount, same costs — but the revenue-generating company buys itself more than three extra months, which is often the difference between raising a round and shutting down. This is why investors grill you on net burn, and why every dollar of early revenue is worth far more than its face value when you are planning a raise.
Examples
Example 1 — A typical seed-stage startup. A SaaS company has $500,000 in the bank, spends $80,000 per month, and collects $20,000 of MRR. Net burn is $60,000, so the runway is 8.3 months. With a planned Series Seed round 18 months away, the cash needed is $1,080,000, leaving a funding gap of $580,000. The founder now knows to start fundraising now rather than in six months.
Example 2 — A pre-revenue team. An app studio has $300,000 saved, spends $50,000 per month, and has not launched yet. With revenue at 0, net burn equals gross burn at $50,000, giving exactly 6.0 months of runway. To reach their 12-month launch milestone they need $600,000 — a $300,000 gap — so they either raise $300,000 or cut spend in half.
Example 3 — A well-capitalized scale-up. A later-stage company holds $2,500,000, spends $150,000 monthly, and books $50,000 of revenue. Net burn is $100,000 and runway is 25 months — more than two years. For a 24-month milestone the cash needed is $2,400,000, and the funding gap is −$100,000, meaning they are already over-funded for the plan and can reinvest, hire, or comfortably wait out a cold market.
FAQ
How is startup runway calculated?
Subtract monthly revenue from monthly expenses to get net burn, then divide your cash balance by that figure: runway = cash ÷ (expenses − revenue). If you have $500,000, spend $80,000, and earn $20,000, your net burn is $60,000 and your runway is about 8.3 months.
What is the difference between gross burn and net burn?
Gross burn is every dollar you spend in a month. Net burn is gross burn minus any revenue you collect. Investors focus on net burn because it reflects the cash you actually lose each month. A company spending $80,000 with $30,000 of revenue has a $50,000 net burn, not an $80,000 one.
How much runway should a startup have?
The common rule of thumb is 12–18 months of runway before a raise, because fundraising typically takes six to nine months. Anything under six months is danger territory — you are negotiating from desperation, which weakens valuation terms. Enter your own numbers above to see where you stand.
What is a good monthly burn rate?
There is no universal number, but sustainable early-stage companies often burn $30,000–$150,000 per month depending on team size and market. What matters is the ratio: burn should be tied to milestones (product launch, revenue targets) rather than headcount growth alone. If you are burning $100,000 a month without measurable progress toward revenue, that is the real warning sign.
How much money do I need to raise to reach my next milestone?
Multiply your net monthly burn by the number of months until your milestone, then subtract your current cash. If net burn is $60,000 and you need 18 months, you need $1,080,000 in total. With $500,000 already in the bank, the funding gap is $580,000 — that is your minimum raise target, plus a buffer for delays.
What happens if my revenue exceeds my expenses?
Your net burn becomes zero or negative, which means you are break-even or profitable and your runway is effectively unlimited. At that point fundraising becomes optional rather than urgent, and you can choose between raising aggressively for growth or staying self-funded.
Should I include my next payroll in the runway calculation?
Yes — expenses should reflect your realistic forward plan, not last month's actuals. If you have signed offers, new hires starting next month, or an upcoming annual software renewal, build those into the monthly expenses figure so the runway reflects reality, not a rosy past.
Disclaimer
This startup runway calculator is provided for informational purposes only and does not constitute financial, investment, accounting, or legal advice. Runway estimates depend entirely on the accuracy of the cash, expense, and revenue figures you enter; actual burn can change with hiring, fundraising, market conditions, and customer behavior. Always confirm your financial position with a qualified accountant or advisor before making funding or spending decisions.