Burn Rate Calculator

Calculate gross and net burn, and how long your cash will last.

What the Burn Rate Calculator does

Burn rate is how fast a company consumes cash. Gross burn is total monthly spending; net burn subtracts revenue. Runway is how many months of net burn your cash covers — the single most important number for an unprofitable business.

Formula

  • Gross burn = Monthly expenses
  • Net burn = Monthly expenses − Monthly revenue
  • Runway = Cash ÷ Net burn (adjusted for growth in both)

Inputs explained

InputUnitRequiredNotes
Cash in the bankselected currencyYesAccepts more than 0.
Monthly expensesselected currencyYesAccepts more than 0.
Monthly revenueselected currencyOptionalAccepts 0 or more.
Monthly revenue growth%Optional
Monthly expense growth%Optional
Currencyone of 10 optionsOptional

How to use it

  1. Choose Currency.
  2. Enter Cash in the bank and Monthly expenses.
  3. Optionally add Monthly revenue, Monthly revenue growth and Monthly expense growth.
  4. Select Calculate.

Worked example

$900,000 in the bank, $145,000 monthly expenses, $62,000 revenue growing 8% a month.

Cash
900000
Expenses
145000
Revenue
62000
Revenue growth
8

Net burn $83,000 today, but growing revenue extends runway well beyond the naive 10.8 months.

Frequently asked questions

What does "default alive" mean?

Paul Graham's term for a startup that reaches profitability on its current growth trajectory before the money runs out — without needing to raise again.

How much runway should I keep?

At least 18 months after a raise. Below six months, fundraising leverage collapses and you negotiate from weakness.

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