Monthly cash burn after gross profit contribution.
Cash Runway Calculator
Estimate how many months a business can operate before cash runs out.
Question answered
How long can the business operate before cash reaches the minimum safe floor?
Numbers needed
Current cash, Monthly revenue, Monthly revenue growth, Gross margin, Fixed monthly costs, Variable monthly costs, Planned one-time expenses, Minimum cash buffer, Target runway months
Inputs
Outputs
WarningPrimary outputs
Months before cash reaches zero under the current burn profile.
Supporting outputs
Gross profit available to cover operating costs.
Recurring operating costs plus modeled variable monthly costs.
Months before cash reaches the minimum cash buffer.
Monthly cost reduction needed to reach target runway.
Revenue required to cover operating costs at the modeled margin.
Revenue gap to cash break-even.
Recommended next move
WarningRunway is below the target
Current assumptions provide 8 months of runway and 6.67 months before the cash buffer is crossed, below the 12 month target.
Cost reduction has more immediate leverage
The target runway needs about $5,000.00 of monthly burn improvement. Cost reduction is the more direct lever unless revenue growth improves materially.
24-month cash projection
Compare how the result changes when a key assumption moves.
| Month | Revenue | Gross profit | Operating cost | Net burn | Ending cash |
|---|---|---|---|---|---|
| 1 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $105,000.00 |
| 2 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $90,000.00 |
| 3 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $75,000.00 |
| 4 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $60,000.00 |
| 5 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $45,000.00 |
| 6 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $30,000.00 |
| 7 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $15,000.00 |
| 8 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | $0.00 |
| 9 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$15,000.00 |
| 10 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$30,000.00 |
| 11 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$45,000.00 |
| 12 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$60,000.00 |
| 13 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$75,000.00 |
| 14 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$90,000.00 |
| 15 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$105,000.00 |
| 16 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$120,000.00 |
| 17 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$135,000.00 |
| 18 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$150,000.00 |
| 19 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$165,000.00 |
| 20 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$180,000.00 |
| 21 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$195,000.00 |
| 22 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$210,000.00 |
| 23 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$225,000.00 |
| 24 | $50,000.00 | $25,000.00 | $40,000.00 | $15,000.00 | -$240,000.00 |
Operator context
Use this when
- Use before hiring, increasing spend, or taking on fixed commitments.
- Use when burn rate, revenue growth, or one-time expenses are changing.
- Use to decide whether cost reduction, revenue acceleration, or financing is urgent.
Interpretation rules
Short runwayCritical
If buffer-adjusted runway is below the target, act before commitments become irreversible.
Forecast cadenceWarning
Low runway should trigger a 13-week cash forecast and weekly operating review.
Operator notes
- Model unrestricted cash only; do not include restricted reserves unless they can fund operations.
- Financing and major cost reductions usually need lead time, so act before the runway is nearly exhausted.
Watch for
- Ignoring one-time expenses can overstate runway.
- Using revenue instead of gross profit understates burn for low-margin businesses.