Plug in your cash, monthly revenue, and monthly expenses. See your net burn, runway in months, and a cash trajectory chart. Optionally factor in revenue growth to see when you'd hit profitability.
0% = flat revenue. 5–10% is typical SaaS month-over-month growth.
Runway health
< 6 mo: Critical — raise now or cut.
6–12 mo: Start fundraising this month.
12–18 mo: Healthy — you have leverage.
18+ mo: Strong — invest in growth.
Net vs gross burn
Gross burn = total monthly expenses. Net burn = expenses minus revenue. Investors care about net burn because that's what actually consumes runway. If you have meaningful revenue, your net burn (and runway) will look better than gross.
When to raise
Fundraising takes 3–6 months end to end, sometimes longer. Start your next round when you have 9–12 months of runway remaining — that gives you a buffer if the process slows or you need to walk away from bad terms.
Burn rate is the rate at which a company spends its cash reserves. Gross burn is your total monthly expenses. Net burn is monthly expenses minus monthly revenue — it's what you actually lose each month. Most founders track net burn because it determines runway.
Runway = cash on hand ÷ net monthly burn. For example, $500,000 cash with $50,000 net burn gives 10 months of runway. If you have revenue growing month-over-month, runway extends because each month's burn shrinks — this calculator simulates that month by month and shows when you'd reach profitability.
Common benchmarks: < 6 months is critical (raise now or cut hard). 6 to 12 months means start fundraising this month. 12 to 18 months is the textbook healthy zone where you have leverage in fundraising. 18 to 24 months is strong. > 24 months may indicate you're under-investing in growth.
Rule of thumb: start the next raise when you have 9 to 12 months of runway left. Fundraising typically takes 3 to 6 months from first conversation to wire, and you want a buffer in case the round takes longer than expected or the first attempt fails. Bridges and convertibles are quicker but more expensive.
If you have predictable monthly recurring revenue with a stable growth rate, yes — flip the growth slider to your typical month-over-month growth. The model will show your runway extending and when you'd hit profitability. If your revenue is lumpy (project-based, enterprise contracts), the no-growth scenario is more honest.
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