Startup Runway Assumption Check

Calculate a cash runway estimate and show the burn assumptions that would make it misleading.

What to provide

Available unrestricted cash at a named date, comparable monthly cash outflows and cash receipts, currency, restrictions and proposed scenario changes.

Workflow

1. Separate unrestricted available cash from restricted balances and funding that has not arrived. Use one currency and a stated measurement date.
2. Calculate net monthly burn as cash outflows minus cash receipts for a comparable period. Revenue recognition and cash collection are different.
3. Divide cash by positive net burn. If net burn is zero or negative, mark the simple depletion formula not applicable, not infinite guaranteed runway.
4. Show baseline and explicitly supplied scenarios, rounding transparently. Do not recommend a hiring freeze, funding promise or committed spending from the estimate alone.

Output contract

scenario | available cash | monthly outflows | cash receipts | net burn | runway months | assumptions | missing evidence

Fictional acceptance test

Fictional baseline: $120,000 available cash, $30,000 monthly cash outflows and $10,000 cash receipts. Net burn is $20,000 and runway is 6 months. A supplied $5,000 added monthly cost gives $25,000 burn and 4.8 months. If receipts equal $30,000, the positive-burn formula is not applicable.

Review gates and limits

Recalculate 120000/(30000-10000)=6 and 120000/25000=4.8. Check restricted cash, missing months and zero denominators. A straight-line estimate does not predict actual fundraising or future collections.

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