Startup Runway Calculator
Free startup runway calculator: enter cash balance, monthly net burn, and optional revenue growth to see months of runway and your zero-cash horizon.
Total cash and equivalents available today.
Cash consumed per month after revenue.
Used with the growth rate below. Enter 0 if pre-revenue.
Optional. Expenses are held flat while revenue compounds.
Results
Runway
10 months
Assumes burn holds steady.
At $45,000 monthly net burn, your $450,000 gives you about 10 months of runway - below the 12–18 months typically targeted between raises.
Free and instant - nothing is stored or sent. Estimates for planning purposes, not accounting, tax, or investment advice.
Runway is the number of months until the bank account hits zero at the current pace of spending. It is the deadline every other plan lives inside: hiring, product bets, and fundraising timing all key off this one number.
The simple version is cash divided by net burn. This calculator also models an optional monthly revenue growth rate - because a business whose revenue is compounding toward its expense line has more runway than the static division suggests, and may never hit zero at all.
What runway measures
Runway = cash ÷ monthly net burn. With $450,000 in the bank and $45,000 of monthly net burn, runway is exactly 10 months. The zero-cash date is that many months out - a calendar deadline, not an abstraction.
Runway is only as honest as the burn number behind it. Use net burn measured from actual bank balances over several months, not last month alone, and re-run the number monthly.
How revenue growth changes the picture
If revenue is growing while expenses stay flat, each month’s burn is a little smaller than the last. This calculator holds total expenses constant (current net burn + current revenue) and compounds revenue at your growth rate, then counts months until cash runs out.
When growth is fast enough, revenue crosses the expense line before the cash does - the "default alive" trajectory. In that case the calculator reports 120+ months rather than pretending to know the exact crossover behavior years out.
How to interpret the result
Between raises, 12–18 months of runway is typically targeted: long enough to hit milestones and run a fundraise from strength. Under six months, fundraising or decisive cost action is urgent - a raise commonly takes three to six months end to end.
Treat the zero-cash date as a planning trigger, not a prediction. Burn drifts, revenue surprises in both directions, and one missed enterprise payment can move the date by a month. The teams that survive tight cash are the ones who re-forecast every month.
Frequently asked questions
How do I calculate startup runway?
Divide total cash by monthly net burn (cash spent minus cash collected, per month). $450,000 of cash at $45,000 of monthly net burn is 10 months of runway. If revenue is growing, effective runway is longer - this calculator models that with a monthly growth rate.
How many months of runway should a startup have?
A range of 12–18 months between raises is typically targeted, and starting a fundraise with at least 6–9 months remaining is commonly advised, since raises often take three to six months. Bootstrapped businesses frame it differently: months of reserves rather than months to a round.
What is "default alive"?
A company is default alive if, at current growth and spending, revenue overtakes expenses before cash runs out - it can reach profitability without raising again. If not, it is default dead and the plan depends on future funding. This calculator flags the default-alive case when growth outpaces burn.
Should runway include expected revenue growth?
Compute both. The static number (cash ÷ current burn) is the conservative floor to plan around; the growth-adjusted number shows the trajectory. Fund commitments like hiring against the floor, not the optimistic curve - growth can stall, but payroll cannot.
Keep going
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