Cash Runway & Burn Rate Calculator

What this calculator does

This tool tells you how many months of cash you have left at your current spending — your runway — along with your gross and net monthly burn. Enter your cash on hand, monthly revenue, and monthly expenses. It's built for owners and founders who need to know, honestly, how much time the bank balance buys before something has to change.

How it works

Gross burn is your total monthly spending. Net burn is what you actually lose each month after revenue: expenses minus revenue.

Runway = cash on hand ÷ net burn. If revenue is equal to or greater than expenses, you're cash-flow positive and runway is effectively unlimited — the calculator will say so.

A worked example

With $150,000 in the bank, $20,000/month in revenue, and $50,000/month in expenses:

Five months is the window to either grow revenue, cut expenses, or raise capital. Most operators want to start acting well before runway gets that short.

How to read your result

Runway is a planning horizon, not a deadline. A common rule of thumb is to keep at least 3–6 months of operating expenses in reserve, and to begin fundraising or cost-cutting while you still have 6+ months — raising or restructuring under pressure rarely goes well. Watch the trend, too: runway shrinking month over month is a warning even if the absolute number still looks comfortable.

Common mistakes

• ·Using a good month as 'normal.' Base burn on a realistic average, not your best revenue month.
• ·Ignoring lumpy costs. Quarterly taxes, annual software renewals, and one-off purchases distort a single month. Smooth them across the year.
• ·Confusing profit with cash. You can be profitable on paper and still run out of cash if customers pay slowly — watch receivables alongside runway.

Frequently asked questions