Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Runway with growth (months)
120
Status
Default alive — growth outruns burn
Runway at flat revenue (months)
10.9
Current net burn
$55,000
Revenue needed to break even
$85,000
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How to use this
- 1Enter cash in bank ($).
- 2Enter monthly expenses ($).
- 3Enter monthly revenue ($).
- 4Enter monthly revenue growth (%).
- 5Read your runway with growth (months) on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Runway is cash divided by net burn. This also shows what revenue growth would buy you an extra six months without raising.
Worked example
Using the values the calculator loads with:
Inputs
- Cash in bank: 600000 $
- Monthly expenses: 85000 $
- Monthly revenue: 30000 $
- Monthly revenue growth: 8 %
Results
- Runway with growth (months): 120
- Status: Default alive — growth outruns burn
- Runway at flat revenue (months): 10.9
- Current net burn: $55,000
- Revenue needed to break even: $85,000
What each field means
Inputs
- Cash in bank ($)
- The cash in bank used in the calculation, measured in $. Starts at 600000 $ so you have a working example on load.
- Monthly expenses ($)
- The monthly expenses used in the calculation, measured in $. Starts at 85000 $ so you have a working example on load.
- Monthly revenue ($)
- The monthly revenue used in the calculation, measured in $. Starts at 30000 $ so you have a working example on load.
- Monthly revenue growth (%)
- The monthly revenue growth used in the calculation, measured in %. Starts at 8 % so you have a working example on load. Accepted range: 0–60 %.
Results
- Runway with growth (months)
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Status
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Runway at flat revenue (months)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Current net burn
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Revenue needed to break even
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the startup runway & burn calculator work?
Runway is cash divided by net burn. This also shows what revenue growth would buy you an extra six months without raising. The underlying maths is: Runway = cash ÷ (expenses − revenue)
What do I need to enter?
4 values: cash in bank, monthly expenses, monthly revenue, and monthly revenue growth. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the runway with growth (months) result mean?
It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Startup Runway Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/grant-runway
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/grant-runway" target="_blank" rel="noopener">Startup Runway Calculator — RevenueLab</a> (2026).</p>
Source: [Startup Runway Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/grant-runway) (2026).