Default Alive Runway
Simulate whether recurring revenue reaches operating cost before cash runs out.
Description
Default-alive simulation tests whether revenue meets cost before cash depletion within a chosen horizon.
Default-alive simulation tests whether revenue meets cost before cash depletion within a chosen horizon.1
Simulate whether recurring revenue reaches operating cost before cash runs out.
When to use Default Alive Runway
Use this tool to simulate whether recurring revenue reaches operating cost before cash runs out.
Prepare consistently defined customer counts, durations, costs or forecast assumptions. Keep aligned records and monetary amounts on a common period and currency basis.
How to use Default Alive Runway and understand its results
- Prepare consistently defined customer counts, durations, costs or forecast assumptions. Keep aligned records and monetary amounts on a common period and currency basis.
- Enter cashOnHand, currentMonthlyRevenue, monthlyOperatingCost, revenueGrowthFraction, forecastMonths using the field table and calculation rules, then run the tool.
- Read defaultAlive, monthsToBreakeven, cashAtExit. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| cashOnHand | Cash on hand | number | Required |
| currentMonthlyRevenue | Current monthly revenue | number | Required |
| monthlyOperatingCost | Monthly operating cost | number | Required |
| revenueGrowthFraction | Revenue growth fraction | number | Required |
| forecastMonths | Forecast months | number | Required |
Enter nonnegative cash/revenue/growth, positive cost and integer horizon 0–120. Return success month/cash before charging, or −1 and exit cash; stop when cash turns negative.
for month=0…horizon: test revenue≥cost; otherwise charge loss then grow revenue Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| defaultAlive | Default alive | boolean |
| monthsToBreakeven | Minus one if breakeven was not reached before cash ran out or the forecast ended. | number |
| cashAtExit | Cash when breakeven occurs, cash is exhausted, or the forecast ends. | number |
{
"input": {
"cashOnHand": 100,
"currentMonthlyRevenue": 80,
"monthlyOperatingCost": 100,
"revenueGrowthFraction": 0.25,
"forecastMonths": 6
},
"output": {
"defaultAlive": true,
"monthsToBreakeven": 1,
"cashAtExit": 80
}
}Limitations and assumptions
Inclusive iteration can charge horizon+1 loss months. False can mean horizon exhaustion with cash remaining. No financing or cost growth is modeled.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Revenue Projection Growth Screen: Flag forecast months whose month-over-month revenue growth exceeds a chosen limit. For a complementary task, use Ramen Profitability Gap: Compare founder personal income with living costs and compute cash runway if short.
References
-
Default Alive Runway — tool.io
Similar or alternative tools
- Revenue Projection Growth Screen
Flag forecast months whose month-over-month revenue growth exceeds a chosen limit.
- Ramen Profitability Gap
Compare founder personal income with living costs and compute cash runway if short.