Startup Essential

Runway Calculator

What Is This Calculator?

Runway is the number of months a startup can continue operating before its cash balance hits zero. Static runway assumes current burn rate stays constant — just divide your cash by your monthly net burn. Dynamic runway accounts for revenue growth and expense growth, which gives a much more realistic picture because few startups have flat revenue. The critical insight is that runway is not just a survival metric — it dictates your strategic options. With 18+ months of runway, you can experiment, iterate, and wait for the right fundraising window. With 12 months, you should be planning your next raise. With 6 months, you are in emergency mode — fundraising under duress with leverage shifting heavily to investors. The "fundraise deadline" output is arguably the most important number this calculator produces: it tells you the latest date you can begin raising capital (assuming a 5-7 month process) and still close before running out. Most founders start fundraising too late because they anchor on the zero-cash date rather than counting backward from it. According to First Round Capital's data, the median time from first partner meeting to wire transfer is 5.5 months, and that assumes a warm introduction and a company with clear traction. Cold outreach adds another 1-2 months. Build that timeline into your planning or risk discovering the math too late to change the outcome.

How to Use This Calculator

Enter Cash and Burn

Add Revenue and Growth Assumptions

Compare Static vs. Dynamic Runway

Note Your Fundraise Deadline

Key Concepts

Static Runway

Cash balance divided by monthly net burn, assuming no change in revenue or expenses. This is the worst-case scenario and the number to use for conservative planning.

Dynamic Runway

Runway calculated with projected revenue growth and expense growth over time. More realistic but depends heavily on assumptions — overly optimistic growth projections will make this dangerously misleading.

Default Alive / Default Dead

Paul Graham's binary test: if your current revenue growth rate continues and expenses stay constant, will you reach profitability before running out of cash? Every startup should know its status.

Fundraise Timeline

The typical time from first investor meeting to money in the bank. For seed rounds, 3-5 months is typical. For Series A+, 5-7 months. In a down market, add 2-3 months.

Cash-Out Date

The calendar date when your bank balance reaches zero at current trajectory. This is the hard deadline around which all strategic decisions should be made.

Ramen Profitability

When a startup generates just enough revenue to cover the founders' basic living expenses. Coined by Paul Graham, reaching this milestone eliminates the existential urgency of fundraising.

Expert Insights

Build three runway scenarios: base case with current growth, bear case with zero revenue growth, and bull case with target growth. Make decisions on base case, plan contingencies around bear case.

Frequently Asked Questions

18-24 months after a funding round is the standard target. Below 12 months, actively fundraise or cut costs. Below 6 months is a crisis — you have likely passed the point where you can raise a normal round, and bridge financing or emergency cuts become necessary.

Static divides cash by current monthly net burn and assumes nothing changes. Dynamic models revenue growth and expense changes over time, recalculating each month until cash hits zero. Dynamic is more realistic but can be dangerously optimistic if growth assumptions are wrong. Always check both.

At least 6-7 months before cash runs out. The average fundraise takes 5-7 months. Starting with less than 6 months of runway means investors know you are desperate, which shifts all leverage to them and often results in worse terms or failure to close.

No. Only count cash in the bank. Verbal commitments, signed term sheets, and even signed subscription agreements do not count until the money has wired. Deals fall through. Counting committed capital as runway has killed companies.

Three levers: increase revenue (raise prices, upsell existing customers), decrease expenses (renegotiate contracts, cut underperforming marketing, reduce headcount), or increase cash efficiency (collect receivables faster, negotiate longer vendor payment terms).

Results are estimates for educational purposes only. Actual amounts may vary based on your specific financial situation, market conditions, and other factors. This calculator does not constitute financial advice.