Divide your ready cash by what you would burn each month. $18,000 with $4,000 of spending and $1,000 of income still coming in lasts 6 months. Enter your numbers to see your runway and what a 3, 6, or 12 month emergency fund takes. Free, no sign-up.
What this leaves out: losing a job can add costs, like health insurance you used to get through work. Add those to monthly spending. The result also ignores interest on your savings, which is small over a few months.
Say you have $18,000 in ready cash and normally spend $4,000 a month. Cutting to essentials only would bring spending down to $3,200.
Cutting to essentials and keeping some income coming in turns 4.5 months into about 8. Run the calculator twice, once with normal spending and once with essentials only, to see both.
Runway is how many months your ready cash would last if your income stopped or dropped. The calculator first finds your monthly burn: monthly spending minus any income that keeps coming in.
Then it divides your ready cash by that burn: months of runway = ready cash ÷ (monthly spending − ongoing income). If ongoing income covers your spending, your savings last indefinitely.
The emergency fund targets multiply your monthly burn by 3, 6, and 12 months, so you can see how much cash each target takes and how far you are from it. If ongoing income already covers your spending, the targets use your full monthly spending instead, in case that income stops too.
Three to six months is a common starting point. People with variable income, a single income household, or a specialized job that takes longer to replace often aim for more.
Subtract any income that would keep coming in from your monthly spending to get your monthly burn, then divide your ready cash by that number. For example, $18,000 in savings with $4,000 of spending and $1,000 of ongoing income lasts six months.
Money you can reach within days without penalties or selling investments at a bad time: checking, savings, and money market accounts.
Try both. Your current spending shows your honest runway. A lean budget, with only essentials, shows how far you could stretch it in an emergency.
Add severance to ready cash once it is in hand, after tax. Add unemployment benefits to ongoing income only if you expect to qualify. Amounts, waiting periods, and how long benefits last vary by state.
Not well. It assumes cash that is not invested and spending that stays flat. Retirement drawdown needs investment returns, inflation, and taxes in the math, so use a retirement calculator for that.
Related reading: Months of runway, Emergency funds that still move, Three months is a starting line, Job change on the timeline, Savings rate is the lever, Freelance without living on hope. More free calculators at theflan.app/tools.