Phase 4 · General Utility
Emergency Fund Calculator
The buffer between a bad month and a financial spiral. Size your target on real essentials, see exactly how protected you are today, and get a month-by-month date to fully funded.
How big should my emergency fund be?
Size it on essential monthly spending, not total spending: target = monthly essentials × months of coverage. Three months suits a stable dual-income household; six is the common default; nine to twelve fits variable income, a single earner, or a long hiring cycle in your field.
- Worked example (defaults on this page): $4,000 of monthly essentials at 6 months of coverage is a $24,000 target. With $5,000 saved you currently hold 1.25 months of runway.
- Contributing $500/month into a 4% APY account reaches fully funded in 35 months — just under 3 years.
- Essentials means housing, food, utilities, insurance, transport and minimum debt payments. Including discretionary spending inflates the target and delays the date you are actually protected.
- Keep it liquid and separate — a high-yield savings account, not investments. The 4% APY here roughly offsets inflation; chasing more return risks the balance being down exactly when you need it.
Under the hood
The math, fully exposed
We size the target on essentials, then grow your balance month by month until it's reached:
Target fund = monthly essential expenses × months of coverage
Coverage now = current savings ÷ monthly expenses
Each month: balance = balance × (1 + APY ÷ 12) + contribution
Fully funded = first month the balance reaches the target
- Essentials, not lifestyle: sizing on must-pay costs keeps the target reachable — discretionary spending pauses in a real emergency.
- Coverage is the real score: the months your current savings would last matters more than the dollar amount — it's what stands between you and new debt.
- Interest helps a little: a high-yield rate shortens the timeline modestly, but consistent contributions do the heavy lifting.
Your directives
What to do next, based on your numbers
Adjust the sliders to generate tailored recommendations.
Answers
Frequently asked questions
How big should my emergency fund be?
The common rule is three to six months of essential expenses — rent or mortgage, food, utilities, insurance, minimum debt payments. Lean toward three months if you have very stable income and few dependents; toward six or more if your income is variable, you are a single earner, or your job is less secure. The number is months of essential spending, not your full lifestyle budget.
What counts as an essential expense?
The costs you could not stop paying if your income vanished: housing, groceries, utilities, transportation, insurance premiums, and minimum payments on debt. Leave out discretionary spending — dining out, subscriptions, travel — because in a genuine emergency those are the first things to pause. Sizing the fund on essentials keeps the target realistic and reachable.
Where should I keep my emergency fund?
In a high-yield savings account — fully liquid, FDIC-insured, and earning a real return while it waits. The fund's job is safety and instant access, not growth, so it does not belong in stocks (which can drop 30% exactly when you need the cash) or in a CD that penalizes early withdrawal. A HYSA lets it keep pace with inflation without risking the principal.
Should I build my emergency fund before investing or paying off debt?
A small starter buffer (often $1,000–$2,000) comes first, so a surprise does not push you into new debt. After that, paying off high-interest debt usually beats growing the fund further, since that interest is a guaranteed loss. Once high-interest debt is gone, finish the full fund before ramping up investing. This is an educational model, not financial advice.