Finance & planning

Burn Rate Calculator

Compare monthly operating outflows with revenue and estimate cash runway.

Free, no sign-upRuns in your browserReviewed October 2026Formula & methodology
US dollars
US dollars
US dollars

Results update as you type. Your numbers stay in this browser.

Monthly net burnExample$10,000
Monthly gross burn
$30,000
Cash runway
12 months

Understand the result

What is burn rate?

Burn rate is how fast a company spends cash. Gross burn is total monthly cash outflow; net burn subtracts monthly cash coming in. With $30,000 of monthly expenses and $20,000 of revenue, net burn is $10,000, so $120,000 in the bank lasts about 12 months.

Gross burnMonthly cash expenses
Net burnMonthly cash expenses − Monthly cash revenue
RunwayCash balance ÷ Net burn

Example: a seed-stage startup

  1. Cash in the bank: $120,000
  2. Payroll, rent and software: $30,000 a month (gross burn)
  3. Customer payments: $20,000 a month; net burn: $10,000
  4. Runway: $120,000 ÷ $10,000 = 12 months

Fundraising typically takes months, so many founders start well before runway falls under a year.

Common mistakes

  • Using accounting profit instead of cash. Annual software prepayments, inventory purchases and loan principal move cash even when they are not expenses this month.
  • Assuming burn stays flat. Planned hires raise burn; build a month-by-month cash forecast for decisions.
Common questions

Burn Rate FAQ

What is the difference between gross and net burn?

Gross burn is everything you spend in a month. Net burn subtracts the cash you collect, and it is the number that determines runway.

What if revenue exceeds expenses?

Then net burn is zero or negative: the business is cash-flow positive and has no finite runway under this model.

How much runway should a startup keep?

Enough to reach the next milestone and complete a fundraise or reach profitability with a buffer. Many investors suggest planning for well over a year.