FIRE Number Calculator: your shore line.
The one number every FIRE plan orbits: how much you need invested to live off forever. Divide your annual spending by your safe withdrawal rate — that's it.
Your FIRE number is the total invested portfolio that can sustainably cover your living costs forever. The classic shortcut is annual spending × 25 (assuming a 4% withdrawal rate, the inverse of the Trinity Study's safe rate). Above your number, you're financially independent. Below it, you're still accumulating. The math is simple; the lifestyle choice — Lean, Standard, or Fat — is what makes the number feel right for you.
Read the full explainer →Three steps to your number
- 1Pick a lifestyle and spendingChoose Lean / Standard / Fat to load a preset, then drag annual expenses to your real number.
- 2Set your withdrawal rate4% is the Trinity Study default. Lower (3% / 3.5%) is safer; higher (4.5% / 5%) is riskier.
- 3Read your numberThe big number is your shore line. Toggle to reverse mode to ask: “I have $X saved — what can I spend?”
Your numbers
comfortable middle-class spending
That's 25.0× your annual spending — the classic 4% rule. At your current savings growing at 7%, you'd hit it around age 96 if you add nothing more.
Savings trajectory: age 35 → 55
Your savings grow at the real return rate (~3.9%). The dashed line is your FIRE number — the point where compounding alone gets you there.
| SWR | Multiplier | Target portfolio |
|---|---|---|
| 3% | 33.3× | $1,333,333 |
| 3.5% | 28.6× | $1,142,857 |
| 4% | 25.0× | $1,000,000 |
| 4.5% | 22.2× | $888,889 |
| 5% | 20.0× | $800,000 |
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The math, explained.
What is a FIRE number? +
Why 25× and not 30× or 20×? +
Should the number be in today’s or future dollars? +
Does this include Social Security or a pension? +
Is this financial advice? +
How this number is calculated
FIRE number = Annual expenses ÷ Safe withdrawal rate. With $40,000 spending and a 4% SWR, that’s $40,000 ÷ 0.04 = $1,000,000. The withdrawal-rate table multiplies your spending by the inverse of each rate (33×, 28.6×, 25×, 22.2×, 20×).
The contribution table assumes a 7% nominal return and compounds monthly: FV = PMT × [((1+r)ⁿ − 1) / r]. Read why we use 7% average returns or the 4% rule explained.