Startups & SaaS
Runway Calculator
See how many months your startup can survive at the current burn.
Runway Calculator
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How it works
Runway is the answer to the most important startup question: how long until the money runs out? Divide cash on hand by the monthly net burn, and you get the survival horizon in months.
Founders treat runway as a deadline for milestones: product launch, revenue ramp or the next raise. When runway drops below six months, the pressure to act rises sharply, and every dollar of burn reduction buys weeks of time.
Formula
Runway = Cash on hand / Monthly net burn
Net burn = monthly cash out minus cash in. Use the number from the burn rate page.
Worked example
Example: $400,000 in the bank and a $40,000 monthly net burn. Runway = 400000 / 40000 = 10 months. That is the deadline for the next milestone or raise.
WORKED EXAMPLE — DEFAULT INPUTS
What to know
Runway planning is scenario planning. Build three versions: the base case at the current burn, a conservative case with a 20% higher burn, and an optimistic case with revenue growing faster. The differences between them show how much buffer you really have.
Fundraising is hardest when the runway is short, because investors sense the pressure. Raising with 12 months left gives you leverage; waiting until six months leaves the terms to the market. Extend the runway first, negotiate second.
Some teams include a contingency burn line: runway assuming a 25% cost overrun. It is uncomfortable but honest, and it converts an optimistic timeline into a plan that survives reality. Update both numbers monthly, not quarterly.
Recalculate the runway after every raise, hire or pricing change; the horizon shifts fast, and the plan only stays honest when the number is current.
FAQ
How much runway should a startup have?
12-24 months is comfortable for pre-revenue companies raising in uncertain markets. Below 6 months, fundraising becomes a survival exercise with weak leverage.
What if burn changes next month?
Recompute with the new burn. This tool is a snapshot; update it whenever spending or revenue shifts materially.
Should I count committed funding?
Only cash in the bank. Signed but undrawn commitments are uncertain until they land, so count them separately.
How do I extend runway?
Cut burn (renegotiate contracts, pause hires) or raise cash. Every $10,000 of monthly savings on a $400,000 balance adds two and a half months.