Gross burn
Monthly expensesEverything the business pays in a representative month.
Free founder finance tool
Startup runway and burn rate calculator
Enter current cash, monthly expenses, and monthly revenue. Get gross burn, net burn, runway in months and days, a cash-zero date, and a simple decision scenario.
Startup runway = current cash ÷ monthly net burn. Monthly net burn is expenses minus revenue. If revenue covers expenses, this static model shows that cash is not currently depleting.
Your amounts stay in this browser. No signup is required. Entered financial values are not transmitted or stored. Piveth may measure page usage and, when you calculate, a coarse anonymous category—not the amounts.
Estimated runway—
— · Cash-zero estimate: —
Gross burn—
Monthly revenue—
Net burn—
Revenue coverage—
Cash projection24 months, static net burn
Your entered scenario—
—
—If expenses fall 10%—
If revenue rises 10%—
The calculation
Gross burn, net burn, and runway answer different questions.
Net burn
max(0, expenses − revenue)The amount by which operating cash out exceeds operating cash in.
Cash runway
Current cash ÷ net burnThe number of months cash lasts if the entered monthly pattern remains static.
Revenue coverage
Revenue ÷ expenses × 100The percentage of monthly expense currently covered by operating revenue.
Why this definition?
Carta defines gross burn as monthly expenses and net burn as gross burn minus revenue. Brex describes runway as current cash divided by burn rate. Stripe likewise frames burn rate as the sustainability signal founders use to estimate operating time.
Sources: Carta burn rate calculator, Brex startup runway guide, and Stripe burn rate guide.
Worked example
₹2,00,000 cash with ₹38,420 expenses and ₹12,000 revenue.
“How long can this business operate if nothing changes?”
1Gross burn
₹38,420 monthly expenses.
2Net burn
₹38,420 − ₹12,000 = ₹26,420.
3Runway
₹2,00,000 ÷ ₹26,420 = about 7.6 months.
4Decision
Model a cost cut, hire, or revenue change before committing.
Capital is not revenue.
A founder contribution, loan, or investment can increase current cash, but it should not inflate operating revenue or operating performance. This distinction matches Piveth’s ledger and finance-truth model.
Limits
What this estimate does not know.
- Whether customer invoices will actually be collected on time.
- Whether payroll, tax, infrastructure, or marketing costs will change.
- Whether new financing, debt payments, refunds, or one-time purchases will occur.
- Whether monthly revenue is recurring, seasonal, concentrated, or uncertain.
- Whether accounting adjustments differ from cash movement.
Use a representative monthly average when one month is unusually high or low. Recalculate after material hiring, pricing, financing, or revenue changes. This tool is educational and does not replace accounting or professional financial advice.
Runway questions
Direct answers for founders.
How do you calculate startup runway?
Subtract monthly revenue from monthly expenses to get monthly net burn, then divide current cash by net burn. Example: ₹2,00,000 ÷ ₹26,420 equals about 7.6 months.
What is the difference between gross burn and net burn?
Gross burn is total monthly cash expenses. Net burn is expenses minus monthly operating revenue. Net burn is the cash-loss rate used by this runway calculator.
Should founder capital be counted as monthly revenue?
No. Founder contributions and investment are financing inflows, not operating revenue. Add usable financing to current cash, but keep it out of monthly revenue.
What happens when revenue covers monthly expenses?
Net burn becomes zero, so this static model does not produce a cash-zero date. That is not a promise of permanent solvency because future cash flows can change.
Does this calculator store my financial amounts?
No. Calculations happen in your browser. Piveth may measure page usage and a coarse anonymous category such as “6–12 months runway,” but it does not send the amounts entered here.
Is this a financial forecast?
No. It is a static scenario estimate, not an accounting statement or forecast. It excludes changing costs, collection timing, taxes, debt, and future financing unless reflected in your inputs.
From estimate to operating habit
Runway becomes useful when every project stays current.
The calculator gives one static answer. Piveth helps founders record capital, expenses, and revenue by project, then review the result as the ledger changes.