The Monthly Burn Calculator measures the average amount of cash a business used per month over a selected period. Instead of adding expense categories, it starts with beginning and ending cash, which makes it practical for a quick check against bank balances or management reports. It also shows total cash used, a daily equivalent, and an indicative runway based on ending cash.
Because changes in cash can include more than normal operations, the result should be interpreted carefully. New funding, debt proceeds, tax payments, equipment purchases, and owner distributions can distort the average. For the most useful figure, adjust the balances or measurement period to exclude exceptional transactions. The calculator is especially helpful for founders and finance teams tracking whether recent spending changes are actually reducing cash consumption.
Use the cash balance at the first date in the period.
Use the comparable balance at the final date.
Enter the elapsed months, including decimals for partial months.
A negative result means cash increased rather than decreased.
Runway is calculated only when monthly burn is positive.
Where:
Assumptions: Cash changes are treated as operating burn. Financing proceeds, debt draws, major asset purchases, and other exceptional cash movements should be removed for a cleaner operating measure.
The main result is an estimate based on the values entered and should be interpreted together with the supporting metrics shown.
Use consistent periods and units, and replace planning assumptions with observed data when available.
Given:
Calculation:
Cash used = $250,000 − $190,000 = $60,000. Monthly burn = $60,000 ÷ 3 = $20,000.
Result: Average monthly net burn is $20,000.
At the same burn rate, the $190,000 ending balance represents about 9.5 months of runway.
No. Net burn reflects the change in cash and therefore incorporates cash inflows as well as outflows. Expenses alone do not show how much cash was replenished by revenue.
The result becomes a monthly cash gain. This can reflect profitable operations or an external cash inflow that should be removed for analysis.
Usually no. Use cash that is available for operations so the runway estimate is meaningful.
Yes. Enter the period as a decimal number of months, but very short periods may be unusually volatile.
Subtract the financing proceeds from ending cash, or use balances immediately before and after the financing, to avoid understating burn.