Burn Rate Calculator

Burn rate is a cash metric, not an accounting one. Gross burn is total monthly cash out the door; net burn subtracts monthly cash revenue collected, and it is net burn that consumes the bank balance. Runway is simply cash divided by net burn, expressed in months, and adding those months to today gives the zero cash date. The reason cash rather than net income is used is timing: revenue booked on accrual terms may sit in receivables for 30 to 90 days, prepaid annual contracts deliver cash long before the revenue is recognized, and deferred revenue is a liability that has already funded payroll. For most early-stage technology companies payroll and contractors account for roughly 60 to 80 percent of gross burn, which is why headcount is the primary lever on runway. Investor convention treats 18 to 24 months of runway as comfortable after a round, 12 months as the point to start raising given that a process typically takes three to six months from first meeting to wired funds, and under six months as distress, because a short runway transfers negotiating leverage to the buyer of your equity. The obvious limitation of a static calculation is that it assumes flat revenue and flat spending. A company growing revenue each month has more real runway than the division suggests, while one hiring on a plan has less. Capital expenditure, annual insurance premiums, and tax payments are lumpy and can move the zero cash date by weeks.

Burn rate entered common financial vocabulary during the American venture capital expansion of the 1980s and 1990s, particularly in the personal computer and internet sectors where companies raised equity to fund years of losses before revenue existed. The underlying discipline is much older: cash budgeting and short-term cash forecasting were established treasury practice well before, and the US accounting profession made cash flow reporting mandatory when the Financial Accounting Standards Board issued Statement No. 95 in 1987, requiring a statement of cash flows in place of the earlier funds statement. The dot-com collapse of 2000 and 2001 turned burn rate into a headline metric, as publicly listed companies with large market capitalizations exhausted their reserves within quarters and the phrase became shorthand for the gap between spending and viability. The vocabulary was sharpened again by startup accelerators in the following decade. Paul Graham's 2015 essay Default Alive or Default Dead posed the question in its now-standard form: whether a company reaches profitability on its current trajectory before its existing cash runs out, given current growth and burn. Y Combinator, First Round and similar institutions embedded monthly burn, runway, and zero cash date into standard investor reporting templates, and the 2022 funding contraction pushed many companies to recalculate runway and reduce headcount accordingly.