Startup Runway Calculator

How This Calculator Works

Runway is how many months a business can keep operating before it runs out of cash, given its current cash on hand and net burn rate. Enter your cash on hand, monthly expenses, and (if any) monthly revenue, and this calculator shows your runway in months and the projected calendar date you’d run out of cash at the current rate.

Runway is one of the most-watched numbers at any pre-profitability company, since it sets a hard deadline: either revenue needs to grow, costs need to come down, or more money needs to be raised before the cash runs out. A business whose revenue already covers its expenses has no burn at all — it’s the net gap between the two that determines how long the clock actually runs.

The Formula

$$\vD{\text{Net Monthly Burn}} = \vA{\text{Monthly Expenses}} - \vB{\text{Monthly Revenue}}$$ $$\text{Runway (months)} = \frac{\vC{\text{Cash on Hand}}}{\vD{\text{Net Monthly Burn}}}$$

When monthly revenue meets or exceeds monthly expenses, net burn is zero or negative — cash on hand isn’t depleting, so there’s no runway figure to compute.

Worked Example

$500,000 in cash on hand, $70,000 in monthly expenses, and $20,000 in monthly revenue:

1. Net monthly burn: $\vA{70{,}000} - \vB{20{,}000} = \vD{\$50{,}000}$.
2. Runway: $\vC{500{,}000} \div \vD{50{,}000} = 10 \text{ months}$.

At this rate, the business has 10 months before its cash on hand runs out — assuming expenses and revenue both stay at their current levels the whole time.