Burn Rate Calculator — Startup Runway
Find out how fast your startup is spending cash and how long the money will last. Enter your cash balance, monthly (or quarterly) revenue, and expenses to see your gross burn, net burn, and runway in months.
Expense / revenue period
Estimated months before cash reaches zero at current net burn rate
- 1
Net burn per period
120,000 − 50,000 = 70,000Cash actually consumed from reserves each period (expenses minus revenue). - 2
Runway in months
500,000 ÷ 70,000 = 7.1
How does this calculator work?
Gross burn = total monthly expenses; net burn = expenses minus revenue. Runway = cash on hand ÷ net burn. A startup with $500k cash, $120k/month expenses, and $50k/month revenue has a net burn of $70k and roughly 7.1 months of runway.
Formula
How this is calculated
Burn rate is the speed at which a company consumes its cash reserves. Gross burn is the total amount spent per period (all operating expenses). Net burn subtracts any revenue: Net burn = Expenses − Revenue. This is the real cash drain — the rate at which your bank balance declines.
Runway is how long the company can operate at the current burn rate before running out of money: Runway = Cash on hand ÷ Net burn per month. If net burn is zero or negative (revenue ≥ expenses), the company is cash-flow positive and has infinite runway.
This model assumes burn rate and revenue are constant. In practice they change every month, so treat the runway figure as a planning estimate rather than a precise forecast. Many investors consider 18 months of runway a safe buffer; 12 months or fewer is typically considered a fundraising trigger.
Frequently asked questions
Gross burn is the total cash spent each period, regardless of revenue. Net burn is gross burn minus revenue — it is the actual decrease in your cash balance. Investors usually care about net burn because it shows how fast the company is consuming its reserves.
There is no universal answer — it depends on the stage and growth rate. The general rule is to have at least 12–18 months of runway at all times. If your net burn gives you less than 12 months of cash, many advisors suggest either cutting costs or starting a fundraise immediately.
Yes — any cash paid out is part of gross burn. Many early-stage founders take below-market salaries or no salary at all to reduce burn. Once you include market-rate salaries for all roles, your gross burn typically rises significantly.
Also known as
TG we-Calculate Editorial Team. (2026). Burn Rate Calculator — Startup Runway [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/burn-rate-calculator
TG we-Calculate Editorial Team. "Burn Rate Calculator — Startup Runway." TG we-Calculate. 2026. https://we-calculate.com/calculator/burn-rate-calculator.
TG we-Calculate Editorial Team, "Burn Rate Calculator — Startup Runway," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/burn-rate-calculator
@misc{wecalculate_burn_rate_calculator, title = {Burn Rate Calculator — Startup Runway}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/burn-rate-calculator}}, year = {2026}, note = {TG we-Calculate} }
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