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
Cash and instantly accessible accounts
Tax and market timing
Result
Runway at current spending
5
Runway on essentials only
7
Lean runway incl. selling investments
11
Net monthly burn now
$4,100
Net burn cut to essentials
$3,200
Net proceeds after haircut
$12,000
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Got your number — what next?
Pick one, it takes 20 secondsHow to use this
- 1Enter liquid savings ($) — Cash and instantly accessible accounts.
- 2Enter investments you'd sell if needed ($).
- 3Enter haircut on selling investments (%) — Tax and market timing.
- 4Enter essential monthly spending ($/mo).
- 5Enter discretionary monthly spending ($/mo).
- 6Enter income that continues ($/mo).
- 7Enter one-off severance or payout ($).
- 8Read your runway at current spending on the right — it updates as you type.
- 9Hit Share to keep the scenario or send it to someone.
About this calculator
Runway is the startup metric applied to a household: liquid assets divided by net monthly burn. It is the number that matters when you are considering quitting to freelance, taking a sabbatical, or bracing for a layoff. This calculator separates liquid savings from assets you would rather not touch, subtracts any income that continues (partner's pay, severance, unemployment benefit, side income), and returns runway under both a normal-spending and a cut-back scenario. The gap between those two numbers is your real margin of safety.
Worked example
Using the values the calculator loads with:
Inputs
- Liquid savings: 22000 $
- Investments you'd sell if needed: 15000 $
- Haircut on selling investments: 20 %
- Essential monthly spending: 3200 $/mo
- Discretionary monthly spending: 900 $/mo
- Income that continues: 0 $/mo
- One-off severance or payout: 0 $
Results
- Runway at current spending: 5.37
- Runway on essentials only: 6.88
- Lean runway incl. selling investments: 10.63
- Net monthly burn now: $4,100.00
- Net burn cut to essentials: $3,200.00
- Net proceeds after haircut: $12,000.00
What each field means
Inputs
- Liquid savings ($)
- Cash and instantly accessible accounts
- Investments you'd sell if needed ($)
- The investments you'd sell if needed used in the calculation, measured in $. Starts at 15000 $ so you have a working example on load.
- Haircut on selling investments (%)
- Tax and market timing
- Essential monthly spending ($/mo)
- The essential monthly spending used in the calculation, measured in $/mo. Starts at 3200 $/mo so you have a working example on load.
- Discretionary monthly spending ($/mo)
- The discretionary monthly spending used in the calculation, measured in $/mo. Starts at 900 $/mo so you have a working example on load.
- Income that continues ($/mo)
- The income that continues used in the calculation, measured in $/mo. Starts at 0 $/mo so you have a working example on load.
- One-off severance or payout ($)
- The one-off severance or payout used in the calculation, measured in $. Starts at 0 $ so you have a working example on load.
Results
- Runway at current spending
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Runway on essentials only
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Lean runway incl. selling investments
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Net monthly burn now
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Net burn cut to essentials
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Net proceeds after haircut
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Should I count retirement accounts as runway?
Generally no. Early withdrawals typically trigger income tax plus a penalty, and selling in a downturn locks in losses that compound for decades. Include them only as a genuine last resort, and if you do, apply a large haircut.
Why include a haircut on investments?
Because the account balance is not what lands in your bank. Capital gains tax, bid-ask spreads, and the reality that job losses cluster with market downturns all mean the realisable amount is lower. Twenty percent is a workable default; adjust for your tax situation.
What runway is enough to go freelance?
Most people who make the jump successfully start with at least six months of lean runway plus at least one contracted client, because the first invoices land later than expected — net-30 terms and slow onboarding routinely push first real cash to month two or three.
Does unemployment benefit count as continuing income?
Yes, but model it accurately: benefits are time-limited, capped well below prior earnings for higher earners, and typically taxable. Put the weekly amount in as continuing income and remember it stops before your runway does.
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.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Personal Financial Runway Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/personal-runway-months
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/personal-runway-months" target="_blank" rel="noopener">Personal Financial Runway Calculator — RevenueLab</a> (2026).</p>
Source: [Personal Financial Runway Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/personal-runway-months) (2026).