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Runway is the single most urgent metric for any pre-profitability startup or bootstrapped business: how many months can you continue operating at your current burn rate before you run out of cash?
This calculator computes gross burn (total monthly expenses), net burn (expenses minus revenue), and runway (cash balance ÷ net burn). It also shows the date on which your runway ends and how much monthly revenue growth would extend it.
Burn rate definitions
Gross burn — total monthly operating expenses, regardless of revenue. Net burn — monthly expenses minus monthly revenue. This is what's depleting your bank account. Runway — months until cash reaches zero: Cash ÷ Net Burn.
How to use the runway calculator
- Enter your current cash balance (bank accounts + any credit facilities you can draw).
- Enter your total monthly expenses (payroll, infrastructure, subscriptions, etc.).
- Enter your current monthly revenue.
- Optionally enter a monthly revenue growth rate to model your path to profitability.
Frequently asked questions
When should I start worrying about runway? When runway drops below 12 months, you need to be actively fundraising or cutting costs — fundraising typically takes 3–6 months from first meeting to cash in the bank. Below 6 months, the situation is urgent. Below 3 months, options narrow quickly.
Should I include accounts receivable in my cash balance? Only if they are reliably collectable within 30 days. A conservative runway calculation uses only confirmed cash in the bank, not promises of future payment.
What's a healthy runway for a seed-stage startup? 18–24 months is the generally recommended post-seed runway, which gives enough time to hit the milestones needed for the next round without too-frequent fundraising distraction.