FinelystHow to Calculate Burn Rate: Gross vs Net Burn
How to calculate burn rate step by step: gross vs net burn formulas, a worked example, how to handle one-off costs, and how burn translates into runway.
Startup Runway Calculator
How many months can your startup operate before the money runs out? Enter today's numbers and growth assumptions; the projection updates as you type.
- Runway
- 17.4 monthsCash runs out March 2028
- Gross burn
- €44,000/ month
- Net burn
- €32,000/ month
- Runway at today's burn
- 15.0 months
- Break-even
- Not within the runway
Default dead: at these growth rates the cash runs out before break-even.
Month-by-month projection
| Month | Revenue | Expenses | Net burn | Cash at month end |
|---|---|---|---|---|
| 1 | €12,000 | €44,000 | €32,000 | €448,000 |
| 2 | €12,720 | €44,440 | €31,720 | €416,280 |
| 3 | €13,483 | €44,884 | €31,401 | €384,879 |
| 4 | €14,292 | €45,333 | €31,041 | €353,838 |
| 5 | €15,150 | €45,787 | €30,637 | €323,201 |
| 6 | €16,059 | €46,244 | €30,186 | €293,015 |
| 7 | €17,022 | €46,707 | €29,685 | €263,331 |
| 8 | €18,044 | €47,174 | €29,130 | €234,200 |
| 9 | €19,126 | €47,646 | €28,520 | €205,681 |
| 10 | €20,274 | €48,122 | €27,848 | €177,832 |
| 11 | €21,490 | €48,603 | €27,113 | €150,719 |
| 12 | €22,780 | €49,089 | €26,310 | €124,409 |
| 13 | €24,146 | €49,580 | €25,434 | €98,975 |
| 14 | €25,595 | €50,076 | €24,481 | €74,494 |
| 15 | €27,131 | €50,577 | €23,446 | €51,048 |
| 16 | €28,759 | €51,083 | €22,324 | €28,724 |
| 17 | €30,484 | €51,593 | €21,109 | €7,615 |
| 18 | €32,313 | €52,109 | €19,796 | -€12,181 |
Runs entirely in your browser. No data is sent to a server.
How it works
- Enter the cash you have available today (bank balance, not committed but unpaid funding).
- Add monthly revenue and total monthly expenses. Expenses are your gross burn; expenses minus revenue is your net burn.
- Set monthly growth rates for revenue and expenses. Use 0% for a flat, conservative scenario.
- Read the runway, the month the cash runs out and whether revenue overtakes expenses first. The table shows every month.
FAQ
How do you calculate startup runway?
Divide the cash you have by your monthly net burn (expenses minus revenue). With €480,000 in the bank and a net burn of €32,000, runway is 15 months. This calculator also applies growth rates month by month.
What is the difference between gross burn and net burn?
Gross burn is everything you spend per month. Net burn is gross burn minus the revenue you collect, so it is the amount your cash balance actually shrinks by each month.
How much runway should a startup have?
A common rule of thumb is to start fundraising with at least 6 to 9 months of runway left, because rounds often take several months. Many founders aim for 18 to 24 months after closing a round.
What does default alive mean?
A startup is default alive if, at its current growth and spending, revenue overtakes expenses before the cash runs out. If not, it is default dead and needs to raise money or cut costs.
Is my data saved or sent anywhere?
No. The calculation runs entirely in your browser and nothing is stored or transmitted.
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