Runway Calculator

Enter your cash on hand — the current amount in your business bank account plus any committed undrawn funding. Then enter your monthly revenue (use the current run-rate, not aspirational), monthly fixed expenses (salaries, rent, fixed software), and monthly variable expenses (marketing, cloud infrastructure, payment fees).

The most important input is the monthly revenue growth rate. Be honest. Most startups overestimate growth. If you have been growing 5% month-over-month, do not put in 20% just because the slides say "hockey stick." A growth rate that does not match recent history will give you a falsely optimistic runway picture.

The chart below shows your cash declining month-by-month, alongside revenue and expenses. The red dashed line marks the month you run out of cash. The green dashed line marks the month you become profitable (if applicable).

A starting point for solo founders or seed-stage teams: target 18 months of runway. For Series A and later, 18–24 months is standard. Fundraising typically takes 3–6 months when going well, so anything under 12 months of runway puts you in a weak negotiating position.

Runway is the number of months until your cash hits zero, assuming your current burn rate and revenue growth. If your business is already profitable (revenue exceeds expenses), runway is infinite and the calculator shows "∞".

Net burn is your monthly cash outflow after subtracting revenue. Net burn = expenses − revenue. Investors care about net burn (not gross burn) because growing revenue can dramatically extend runway without raising more capital. A startup with $50K/month gross burn but $40K/month revenue has only $10K of net burn — 5x the runway of one with no revenue at the same gross burn.

Cash needed to reach profitability is a useful planning number. If you can reach profitability before you run out of cash, you do not need to raise more money. If the runway runs out first, you have a clear funding gap to close: the cash needed minus what you have on hand, ideally with a margin of safety.

How to extend runway: the fastest reductions usually come from headcount (the biggest line item for most startups) and discretionary spending (travel, marketing, fancy software). Slower but high-impact: renegotiate vendor contracts, eliminate unprofitable customer segments, automate manual workflows. Aim to extend runway by at least six months when cutting — anything less is not worth the morale hit.

A common scenario: aggressive growth assumption hides reality. If you assume 15% MoM growth but actually grow at 5%, your runway is months shorter than the optimistic chart. Build sensitivity scenarios: best case, expected case, conservative case. Run the calculator with each and plan for the conservative one.

For fundraising: maintain at least 12 months of runway when you start raising, ideally 18+. Founders raising at three months of runway have very little leverage and often end up with worse terms or fail to close in time. Strong founders raise from a position of strength.