Cash flow calculator
See how much cash you keep or burn each month, what your balance will be and how long your cash lasts.
Free to use, no account needed. What you type stays in your browser.
Net cash flow per month
$800.00
Balance at the end
$14,600.00
Lowest balance
$5,000.00
Money in per month
$4,500.00
Money out per month
$3,700.00
You take in more than you pay out each month, so your cash grows.
Cash flow is not profit: it counts when money moves, not when you earn or owe it. These figures repeat the same amounts every month. They are an illustration, not a forecast.
- Money in per month$4,500.00
- Money out per month$3,700.00
Month by month
| Month | In | Out | Balance |
|---|---|---|---|
| 1 | $4,500.00 | $3,700.00 | $5,800.00 |
| 2 | $4,500.00 | $3,700.00 | $6,600.00 |
| 3 | $4,500.00 | $3,700.00 | $7,400.00 |
| 4 | $4,500.00 | $3,700.00 | $8,200.00 |
| 5 | $4,500.00 | $3,700.00 | $9,000.00 |
| 6 | $4,500.00 | $3,700.00 | $9,800.00 |
| 7 | $4,500.00 | $3,700.00 | $10,600.00 |
| 8 | $4,500.00 | $3,700.00 | $11,400.00 |
| 9 | $4,500.00 | $3,700.00 | $12,200.00 |
| 10 | $4,500.00 | $3,700.00 | $13,000.00 |
| 11 | $4,500.00 | $3,700.00 | $13,800.00 |
| 12 | $4,500.00 | $3,700.00 | $14,600.00 |
How this is calculated
Net cash flow is what is left after the money going out is taken from the money coming in. These are the formulas used:
- Net cash flow per month
- N = In − Out
- Balance after m months
- B = O + N × m
- Full months your cash lasts
- floor(O ÷ −N) (N < 0)
In is the money coming in per month (customer payments and other income), Out is the money going out per month (running costs, debt and tax payments, other payments), N is the net cash flow per month, O is the cash at the start and m is the number of months.
Every month is assumed to be the same. Real cash flow moves with seasons, customers who pay late and one-off costs, so use this as a planning illustration, not a forecast. Run it again with weaker figures to see how much room you have.
Every amount is rounded to 2 decimal places before it is added, so the figures shown add up to the cent.
Worked example
With $5,000.00 in the bank, $4,500.00 coming in and $3,700.00 going out each month, you keep $800.00 a month. After 12 months your balance is $14,600.00.
Cash flow questions
What is cash flow?
Cash flow is the money that actually moves in and out of your bank account or till in a period. Net cash flow is money in minus money out. Positive means your cash grows, negative means it shrinks.
How is cash flow different from profit?
Profit counts income and costs when they are earned or owed. Cash flow counts them when the money moves. A business can be profitable and still run out of cash, for example when customers pay late but suppliers and staff must be paid now.
What does "full months your cash lasts" mean?
When your net cash flow is negative, it is your starting cash divided by the monthly shortfall, rounded down to whole months. It shows how long you can carry on before the balance goes below zero if nothing changes.
Why are the figures the same every month?
To keep it simple, the calculator repeats the monthly figures you enter. If your months vary, enter average figures, or try your weaker months to see how much room you have.
Is my information stored or sent anywhere?
No. The calculation runs in your browser. The numbers you enter are not sent to us or saved.
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Results are estimates for planning. They are not financial, tax or religious advice.