Free tool · Cash Pulse
Cash runway calculatorfor small business.
Enter what is in the bank and what moves in and out each month. The calculator shows how many months the cash lasts at today's burn, the month it runs out, and which change buys the most time.
Your numbers
Operating accounts only. Leave out credit lines.
Customer deposits, tax set aside, restricted accounts.
Monthly cash in and out
Money actually received, not invoiced.
Everything paid: payroll, rent, suppliers, loan payments, tax.
Nothing you type leaves this page.
helcyon — cash runway
Example figures
Runway at today's burn
6.0
monthsAbout 183 days.
Stable
Six months or more of cash at this burn. The level is sound, so the thing to watch is the direction.
Available cashAvailable
$75,000
Net burn / moNet burn
$12,500
Runway in daysDays
183
Available cash by month
Straight line at today's burn. Not a forecast.
View as a table
| Month | Available cash |
|---|---|
| Today | $75,000 |
| Month 1 | $62,500 |
| Month 2 | $50,000 |
| Month 3 | $37,500 |
| Month 4 | $25,000 |
| Month 5 | $12,500 |
| Month 6 | $0 |
| Month 7 | $0 |
| Month 8 | $0 |
Helcyon reads this from your transactions, continuously
See Cash Pulse →What moves the number
Your runway with one change applied
Cut cash out by 10%
10.6 months
Lift cash in by 10%
9.0 months
Do both
26.3 months
The method
How to calculate cash runway.
Runway is one division. The work is in getting the two numbers that go into it right.
The formula
Use cash that has actually moved. An invoice you have sent is not cash in until it is paid, and a bill you have received is not cash out until you pay it.
Worked example
A business has $85,000 in the bank, $10,000 of it customer deposits. Cash in averages $42,000 a month and cash out averages $54,500.
Find the cash you can actually use
Start with the operating account balances. Take out anything already committed: customer deposits for work not yet done, tax you have collected or set aside, and restricted accounts.
Average the burn over 90 days
One month misleads. Add up cash paid out and cash received over the last three months and divide each by three. Use money that moved, not invoices sent or bills received.
Divide, then check the direction
Available cash divided by net burn gives months of runway. Then compare last month's burn with the one three months back. Six months and stable is a different reading from six months and falling.
Reading the result
What your runway number means.
The calculator sorts the result into four readings. They are general rules of thumb, the kind a doctor uses for a first look before running the tests.
Under 3 months
Critical
One late customer payment or one unplanned bill can use up the margin. Decide this week what gets cut, collected or financed.
3 to 6 months
Tight
There is time to act, provided the burn is not rising. Check the three-month view before relying on the average.
6 months or more
Stable
The level is sound. Watch the direction, because a long runway that is shortening every month is still a problem arriving.
Cash in exceeds cash out
Cash-flow positive
There is no cash-out date at these numbers. A surplus that is shrinking month to month is the early sign to look for.
These bands are not advice and they are not how Helcyon grades a business. Helcyon reads each business against its own baseline, because six months of cash means something different to a seasonal contractor than it does to a dental practice.
Where a calculator stops
A runway number is only as good
as the day you typed it.
The arithmetic is simple. What makes runway hard to manage is that the inputs move every week, and a calculator only knows what you tell it.
01
It trusts your averages
The result is only as accurate as the monthly figures you entered. Most owners estimate them from memory, and memory is not the bank statement.
02
It is one reading
A single number says where you are today. It does not say whether you were at eight months last quarter or at four.
03
It cannot see what is committed
Deposits owed back as work, tax due next month and a loan payment about to step up all sit inside the bank balance until someone takes them out.
Cash Pulse™ · Vital Sign 1 of 5
The same reading, taken from the transactions.
Cash Pulse is the first of Helcyon's five Business Vital Signs. It reads available cash, burn averaged over 90 days and days of runway from the transactions themselves, and it reports whether that runway is rising or falling. It is a reading of what the transactions show, not a projection.
Connects with the tools you already use
Questions
Cash runway, answered plainly.
What is cash runway?
Cash runway is how long a business can keep operating before its usable cash runs out, at the rate it is currently paying out more than it receives. It is usually stated in months or days.
How do you calculate cash runway?
Divide available cash by net monthly burn. Available cash is what is in the operating accounts minus anything already committed. Net monthly burn is average cash paid out per month minus average cash received. Available cash of $75,000 and a net burn of $12,500 a month is six months of runway.
What is the difference between gross burn and net burn?
Gross burn is everything paid out in a month. Net burn is what is paid out minus what is received. Runway uses net burn, because cash coming in extends how long the balance lasts.
How many months of cash runway should a small business have?
A common rule of thumb is three to six months of operating expenses. The right figure depends on how steady revenue is. A business with recurring monthly revenue can run leaner than one that depends on a few large projects or a seasonal peak. Direction matters as much as the level: six months and falling needs attention sooner than four months and holding.
Why does a profitable business still run short of cash?
Profit is an accounting result and cash is timing. Revenue that is invoiced but not collected, customer deposits already committed to work, inventory purchases and loan principal can all leave a profitable business short of usable cash. Runway reads the cash, not the profit and loss statement.
What if my cash in is higher than my cash out?
Then the business is adding cash each month and has no cash-out date at those numbers. The calculator reports it as cash-flow positive. The three-month view is still worth checking, because a surplus that is shrinking is an early sign.
Does this calculator save or send my numbers?
No. The calculation runs in your browser. Nothing you type is stored or sent to Helcyon.
How does Helcyon measure runway?
Helcyon reads it as part of Cash Pulse, the first of its five Business Vital Signs. From the business's own transactions it works out available cash, burn averaged over 90 days and days of runway, and reports whether that runway is rising or falling. The connection is read-only.
Have the runway read for you.
The calculator gives you today's number once. Helcyon reads it from your books continuously and tells you when it moves.