Burn Rate & Runway Calculator
Cash on hand ÷ monthly net burn = months of runway.
About this calculator
Free burn rate and runway calculator: enter your current cash balance, monthly revenue, and monthly cash expenses to instantly see your net burn, gross burn, and runway in months — with a verdict on whether you should be raising, cutting, or celebrating. Built for solo founders and seed-stage teams who need a quick gut-check before a strategy meeting or before walking into an investor pitch.
A burn rate calculator tells you exactly how many months of runway you have at your current spending level. It's the most-asked metric in any board meeting, fundraising conversation, or strategy off-site at a venture-backed startup. This free burn rate calculator computes both gross burn (total monthly cash expenses) and net burn (after revenue) and divides your current cash balance by net burn to surface runway in months — with a verdict on whether you should be raising, cutting, or celebrating. Built for solo founders and seed-stage teams who need a fast gut-check.
Gross burn vs net burn — the two numbers this calculator returns
Gross burn = total cash expenses per month (salaries, hosting, rent, software, contractors, marketing, everything that leaves the bank account). Net burn = gross burn minus monthly revenue. The burn rate calculator returns both. Why both matter: gross burn measures your fixed operational weight (useful when stress-testing what happens if revenue dropped to zero — a worst-case scenario investors will absolutely ask about); net burn measures your actual rate of cash depletion (which determines runway). Most founders default to net burn when discussing runway; sophisticated CFOs track both.
How to read a runway verdict
Runway = current cash balance ÷ net burn. The burn rate calculator emits one of five verdicts. 18+ months: healthy — you can raise on your terms, not at the market's mercy. 12-18 months: comfortable — start fundraising conversations now, expect 4-6 months to close. 6-12 months: pressure — close the round in the next quarter or cut burn meaningfully. Under 6 months: critical — cut expenses or close a bridge round this month. Cash-flow positive: infinite runway — the rarest and best verdict the burn rate calculator can return.
When to update your burn rate calculator inputs
Burn rate is not a one-time number. Smart founders run the burn rate calculator monthly, ideally on the same day they close their books. Revenue moves; expenses move; one-time payments (annual SaaS renewals, quarterly tax estimates, severance) distort any single-month snapshot. Some teams compute a trailing-three-month average burn instead of point-in-time burn to smooth this out — this burn rate calculator lets you enter any monthly figures, so you can paste in the smoothed value if that's how you track it. The biggest mistake: forgetting to update inputs after a hire, a tool subscription, or a price change. Set a monthly calendar reminder.
Frequently asked questions
What is burn rate?
Burn rate is the rate at which a startup spends cash, usually expressed monthly. Gross burn is total cash expenses per month; net burn is gross burn minus revenue. Net burn determines runway — the number of months before the company runs out of cash at the current spending level — which is the single most-watched number in any startup's finance dashboard.
What's a healthy runway for a startup?
18+ months is healthy and lets you raise from a position of strength. 12-18 months is comfortable but means you should be starting fundraising conversations. Under 6 months is critical and demands either an immediate cut, a bridge round, or both. The burn rate calculator surfaces the verdict automatically based on your inputs.
Does the burn rate calculator account for one-time payments?
No, by design. The burn rate calculator computes burn from your steady-state monthly expense. If you have lumpy one-time payments (annual SaaS renewals, quarterly tax estimates, signing bonuses), smooth them: divide an annual payment by 12 and add to your monthly expenses; divide a quarterly payment by 3. This gives a smoother burn number that's more useful for runway planning.
Should burn rate include founder salaries?
Yes, if you're paying them — even if you're paying yourself $0 today, model the salary you'd take at market and disclose the gap. Hidden subsidies (unpaid founder time, deferred salary, free office space from a relative) make burn look artificially low and lead to bad runway decisions when the subsidy ends.
Related free resources: Break-Even Point calculator · Cash Flow Forecast template
Want this metric in context, not in isolation?
The Unbuilt Lab app runs your idea through a 6-document Blueprint Pack — and the Market Validation doc covers Burn Rate & Runway Calculator against your specific market data, competitors, and unit-economics targets. Not a generic calculator: tailored analysis.