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Startup Finance

Burn Rate and Startup Runway Explained

Burn rate shows how quickly cash is being used. Runway estimates how long current cash can last at that burn rate.

By QuickWebUtility Editorial ยท Published Aug 6, 2026

The quick answer

Burn rate is the speed at which a business uses cash. Runway is the estimated time before cash runs out if burn continues. Startups use both metrics to plan hiring, fundraising, pricing, and cost control.

Gross burn vs net burn

Gross burn is usually monthly expenses before revenue offsets. Net burn is the monthly cash decrease after revenue. If revenue exceeds expenses, net burn can be negative.

gross_burn = monthly_expenses
net_burn = monthly_expenses - monthly_revenue
runway_months = cash_balance / net_burn

Use the Burn Rate Calculator for historical cash movement and the Startup Runway Calculator for forward-looking runway assumptions.

Example

A startup has 120,000 cash, 20,000 monthly expenses, and 5,000 monthly revenue. Net burn is 15,000 per month. Simple runway is 8 months.

Common mistakes

Do not calculate runway from bank balance without upcoming payables. Do not use average monthly revenue when revenue is highly seasonal. Do not ignore payroll taxes, benefits, annual renewals, refunds, or delayed receivables.

Actionable recommendations

Review runway monthly, keep a conservative case, and define trigger points for cost changes or fundraising. Pair runway with break-even analysis and the Break-Even Calculator.

FAQ

How much runway should a startup have?

There is no universal answer. It depends on revenue predictability, fundraising conditions, hiring plans, and the cost of reducing burn.

Can runway be infinite?

If revenue is equal to or greater than expenses, simple runway may be sustainable instead of a depletion date. Keep monitoring cash timing.

Related calculators

Burn Rate Calculator Calculate gross burn, net burn, average monthly burn, cash reduction, and runway. Startup Runway Calculator Estimate runway months, runway date, burn, and cash remaining after selected periods. Break-Even Calculator Find break-even units, revenue, contribution margin, expected profit, and margin of safety.

Related guides

How to Calculate Break-Even Point for a Small Business Break-even tells you how much you need to sell before the business covers its costs. It is a planning floor, not a profit goal. ROI Explained: Formula, Examples, and Common Mistakes ROI compares net gain with the amount invested. It is useful, but only when costs, timing, and risk are handled consistently.