How long the cash lasts,before the wishful math.
Runway is the only deadline that doesn't move. This calculator nets your revenue against your spend, tells you your real burn, and counts the months you have left at this rate — so you can decide to raise, cut, or grow on facts instead of a hunch.
Your numbers
Total cash in the bank right now: the fuel in the tank.
Cash actually collected per month — not bookings, not pipeline.
Everything that leaves the account each month: payroll, tools, rent, ads.
The verdict
Net burn / month
$50,000
Runway (months)
10
Gross burn / month
$80,000
Out of cash in
10
Months until the balance hits zero.
Where the month goes
Runway vs. a healthy 18 months
Below the healthy line. You have room, but the next move should extend it.
Reverse-solve · cut to extend
What trimming expenses buys you
| Scenario | New expenses | Net burn | Runway | Gained |
|---|---|---|---|---|
| Cut 10% | $72,000 | $42,000 | 11.9 mo | +1.9 mo |
| Cut 20% | $64,000 | $34,000 | 14.7 mo | +4.7 mo |
| Cut 30% | $56,000 | $26,000 | 19.2 mo | +9.2 mo |
From today's 10.0 months, each expense cut bends the burn curve. The cleanest extension is usually a mix: trim a little and lift revenue a little until net burn flips negative and the countdown stops for good.
Your move
Turn the runway you have into the runway you need.
10.0 months runway — $500,000 cash at $50,000 net burn/mo.
Send me the burn behind this number and I'll map the shortest path to default alive — which revenue levers move net burn fastest, which line items to cut without bleeding momentum, and where annual prepay can pull a year of cash forward. You leave with a concrete plan to extend the clock, free, whether or not you ever hire me.
Plain English
Burn rate is the speed. Runway is the distance.
Burn rate is how fast you spend cash. There are two flavors that matter. Gross burn is everything going out the door each month — your total expenses, full stop. Net burn is what's left after you subtract the revenue you collect, and it's the number that actually drains the bank. A company spending $80k but pulling in $30k is burning $50k net, not $80k.
Runway is how many months of net burn your cash covers: cash on hand divided by net burn. It's the hardest deadline in the building, because it doesn't negotiate. When the months hit zero, the story ends — regardless of how good the product is or how warm the next round feels.
There's one escape hatch from the countdown: default alive. If revenue meets or beats expenses, net burn is zero or negative, runway is effectively infinite, and you fund your own existence. That's the goal every founder should hold against this number — not 'can we raise again,' but 'can we stop needing to.'
The formula
Runway (months) = Cash on hand ÷ (Monthly expenses − Monthly revenue)
$500,000 in the bank, $80,000 out and $30,000 in each month → net burn $50,000 → 10 months of runway. Lift revenue to $90,000 and net burn goes negative: you're default alive and the clock stops. Same expenses, opposite fate.
What a healthy runway looks like
How much runway is 'enough' depends on stage and how easy it is to raise the next round. The rough norms investors and founders work to:
| Stage | Healthy runway |
|---|---|
| Pre-seed / seed | 18-24 months |
| Post Series A | 24-36 months |
| Default-alive | Profitable |
Source: Startup runway norms (YC / a16z guidance) · 2025
Your runway came back short. Now what?
Under 6 months.
This is a fire, not a forecast. Start the raise yesterday and build a cut plan in parallel — you need a viable company at the runway floor, not a slide deck. Assume fundraising takes 3–4 months and protect that buffer.
6 to 12 months.
Tight enough to act now. Either you have a credible path to a round inside this window, or you cut to extend past 12. Don't coast — runway under a year forces every conversation onto someone else's terms.
High burn, real revenue.
You're closer to default alive than the runway number suggests. Model what 10–20% revenue growth plus a modest expense trim does to net burn — small moves on both sides can flip the sign and end the countdown entirely.
Long runway, flat growth.
Cash isn't the problem; momentum is. A 36-month runway with no growth is just a slow-motion version of the same ending. Spend deliberately into the levers that compound — don't sit on the cash and call it safety.
Eight ways to extend the runway
01Raise revenue, not just cut cost
Every dollar of collected revenue cuts net burn dollar-for-dollar. Closing one more deal a month often beats a round of layoffs and keeps the company growing while it extends.
02Annual prepay over monthly
Move customers to annual contracts paid upfront. It pulls a year of cash into the bank today, which is pure runway you didn't have to raise for.
03Kill zombie SaaS
Audit every recurring tool. Most companies pay for seats and software nobody opens. It's the fastest, least painful expense cut available.
04Slow hiring before cutting heads
A hiring freeze bends the burn curve without the cost and morale hit of layoffs. Freeze first; only cut if the math still doesn't work.
05Renegotiate the biggest line items
Rent, cloud, and your top vendor contracts move the needle far more than trimming snacks. Ask for deferrals and discounts — vendors prefer a paying customer to a churned one.
06Defer non-essential spend
Push rebrands, offsites, and 'someday' projects past the danger zone. Anything that doesn't drive revenue or retention can wait until you're default alive.
07Tighten collections
Net-60 terms and slow invoicing are an interest-free loan you give customers out of your runway. Invoice faster and shorten terms to pull cash forward.
08Get to default alive on purpose
Treat profitability as a deliberate target, not an accident. The point where revenue covers expenses is the only permanent fix for a shrinking runway.
The vocabulary
- Gross burn
- Total cash leaving the business per month — all expenses, before counting any revenue. The full size of the spend.
- Net burn
- Monthly expenses minus monthly revenue. The amount your cash balance actually shrinks by each month; the number that sets runway.
- Runway
- Months of cash left at the current net burn: cash on hand ÷ net burn. The hardest deadline in the company.
- Default alive
- When revenue meets or exceeds expenses, so net burn is zero or negative and runway is effectively infinite. You fund yourself.
- Default dead
- The opposite: on current trajectory you run out of cash before reaching profitability or a raise. The state runway warns you about.
- Cash on hand
- Liquid cash available to spend right now. Not pipeline, not bookings, not committed term sheets — money in the account.
Runway questions, straight answers
Runway in months = cash on hand ÷ net burn, where net burn is monthly expenses minus monthly revenue. $500k in the bank burning $50k net per month gives you 10 months. If revenue covers expenses, net burn is zero or negative and runway is effectively unlimited — you're default alive.
Keep going
A calculator tells you what. A call tells you what to do about it.
Send me the account behind these numbers. I'll tell you straight where the money's leaking and what I'd fix first — free, and you keep it whether you hire me or not.