Startup Runway Calculator: How Many Months of Cash Do You Have?
Runway is the one number every founder should know cold: how many months until the bank account hits zero at your current burn. This calculator takes your cash on hand, monthly revenue, and monthly expenses, then walks forward month by month to give you your runway, your zero-cash date, and the full breakdown. Share the result with your cofounders or investors in one click.
Your numbers
Growth assumptions (optional)
Month-by-month cash walk
| Month | Revenue | Expenses | Net burn | Cash left |
|---|
Net burn is expenses minus revenue: the cash your business consumes each month. The walk stops at 36 months or when cash runs out, whichever comes first. This calculator runs entirely in your browser; nothing you type is sent anywhere.
Model it properly: Seed-Stage Financial Model ($49)
Runway is the headline number. The 36-month model behind it, with hiring plans, revenue scenarios, and investor-ready outputs, is the $49 Seed-Stage Financial Model.
Frequently asked questions
What counts as "cash in the bank"?
Immediately available cash: checking, savings, money market. Not your credit line, not committed but uncalled investor capital, and not the invoice your big customer might pay next quarter.
Should I use gross burn or net burn?
Net burn (expenses minus revenue) is the right number for runway, because revenue offsets what you spend. Gross burn matters when revenue is lumpy or you want the conservative case; run it both ways and know which one you are quoting.
How much runway should a startup have?
Twelve to eighteen months is the standard target after a fundraise: enough to hit the milestones that justify the next round, with buffer for things going slower than planned. Under six months, most founders are already fundraising or cutting.
Does this include my upcoming fundraise?
Only if you enter it in "Planned cash in." Until money is wired, most founders model runway without it and treat the raise as a separate scenario. Hope is not a cash balance.