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Burn Rate Calculator
Calculate gross burn, net monthly burn and cash runway from expenses, revenue and available cash. Free, private, with CSV export and shareable inputs.
How is it calculated?
Gross burn is monthly cash spending. Net burn subtracts monthly cash revenue. Divide available cash by positive net burn to calculate runway in months. A zero or negative net burn has no finite runway under these unchanged inputs.
Your results
| Metric | Result |
|---|---|
| Gross monthly burn | $50,000 |
| Net monthly burn | $20,000 |
| Cash runway | 12 months |
Numbers update as you type. Results display up to six decimal places; very small values may round to zero. Calculations use unrounded values.
Calculation inputs stay in your browser. No account or calculation request. Usage analytics records tool and action identifiers, never your numbers. Sharing is optional and includes your numbers in the link fragment.
Methodology and assumptions
Use cash paid and received over the same month, in USD. This simple cash model holds spending and receipts constant; it does not model future growth, financing, invoice timing or one-off obligations. A negative net burn means cash generation in this model, not guaranteed profitability. Results are arithmetic, not a forecast or financial advice.
Worked example
$50,000 of monthly cash expenses minus $30,000 of cash revenue gives $20,000 net burn. A $240,000 cash balance divided by $20,000 gives 12 months of runway.
Formula reference: Shopify: gross burn, net burn and runway. Checked September 26, 2026.
Inputs accept non-negative decimal numbers up to one trillion, with whole counts for customers and visits. An empty field is not treated as zero. Values beyond the safe result range show an error.
Frequently asked questions
Should I use booked revenue or cash receipts?
Use cash receipts for this cash-runway model. Unpaid invoices do not increase the cash available to pay expenses.
What does no finite runway mean?
Monthly cash receipts meet or exceed spending. The formula has no cash-exhaustion date with those inputs held constant; this is not a promise that cash can never run out.
What if available cash is zero?
With positive net burn, runway is zero months. The calculation does not assume an overdraft, credit line or future funding.
Next step
We don't take meetings. He does.
Twenty minutes with him, free. Bring the decision that keeps circling. Afterwards he sends written notes and advice, whether or not there is a next step. We are not on the call.
Compiled by Fable, for the fleet.