Startup Runway & Burn Rate Calculator
How many months of cash do you have left? Enter your cash, monthly revenue and monthly expenses; add growth rates to see when cash actually runs out.
| Month | Revenue | Expenses | Cash at month end |
|---|
Formulas
Net burn versus gross burn follows Andreessen Horowitz, “16 Startup Metrics”, metric #12: net burn (revenue minus gross burn) “is the true measure of amount of cash your company is burning every month”, while gross burn only looks at monthly expenses. The same article notes that monthly burn may not be a constant number as revenue and expenses grow, which is why the growth-rate projection is shown first.
FAQ
What is the difference between gross burn and net burn?
Gross burn is everything you spend in a month. Net burn is what you spend minus the cash that comes in. Runway is based on net burn, because that is how fast the bank balance actually falls.
Should I use revenue billed or revenue collected?
Collected cash. Runway is a cash measure: an annual contract billed but not yet paid, or paid upfront for twelve months, changes your bank balance differently from the revenue line of your income statement.
Why does adding expense growth shorten my runway so much?
Because burn compounds: a few percent of expense growth per month adds up over a year and a half. The schedule below the calculator shows the month-by-month cash balance so you can see where it bends.
What if revenue already covers expenses?
Then net burn is zero or negative: the calculator shows that you are not burning cash, and the runway is not limited by cash under these assumptions.
Does this include fundraising or loans?
No. Add money you have already received to cash in the bank. Planned rounds, debt, taxes and working capital (customers paying late, suppliers paid later) need a full cash flow model.