Calculator
How long will your cash last?
This calculator shows how many months your cash on hand lasts at your current monthly costs and revenue, and the first month it falls short.
Everything you pay out in a month: rent, software, insurance, supplies, what you pay yourself.
Optional. Leave blank if there are no sales yet.
- Net monthly burn
- Unanswered
- Months of runway
- Unanswered
- First month the cash does not cover in full
- Unanswered
Enter cash on hand and monthly costs to see the runway.
Net burn = monthly costs − monthly revenue.
Runway = cash on hand ÷ net burn, rounded down to a tenth of a month.
How it works
Net burn is what you spend in a month minus what comes in. Runway is how many months of that burn your cash covers.
net burn = monthly costs − monthly revenuerunway = cash on hand ÷ net burn
Runway rounds down to a tenth of a month. The month shown is the first one the cash can't cover in full, counting this month as the first month of costs. If revenue covers costs, the cash is not being used up and there is no run-out month.
This is a straight-line estimate from the numbers entered. Real costs and sales move from month to month, so run it again when they change.
A worked example
A small shop with a lease has $18,000 in the bank. Rent, utilities, insurance, and restocking come to $4,500 a month, and sales bring in $1,500 a month so far.
Net burn is $4,500 − $1,500 = $3,000 a month. Runway is $18,000 ÷ $3,000 = 6.0 months. Starting in January, the cash covers January through June, and July is the first month it falls short. These are illustrative numbers, not typical costs.
Common questions
What should go in monthly costs?
Everything that leaves the account in a normal month: rent, software, insurance, supplies, loan payments, and what you pay yourself to live on. Leaving out your own pay makes the runway look longer than it is.
Should cash on hand include money for one-time purchases?
No. Take out what you have already set aside for equipment, a deposit, or first inventory, and enter what is left. The startup cost calculator handles those one-time costs.
Why does it say the cash is not being used up?
Your revenue matches or beats your costs, so the numbers entered never draw the cash down. The calculator says so instead of showing an endless runway.
How much runway is enough?
There is no single right number. Compare the runway with how long you expect it to take for revenue to cover costs, and leave room for that estimate to be wrong.
To see what to count before you open, read How much does it cost to start a business? If cash is tight from the start, read How to start a business with no money.