What is a FIRE number?
Your FIRE number is how much you need invested to live off your portfolio for good: your yearly spending divided by your withdrawal rate. At the common 4% rate that's 25 times spending, so $40,000 a year needs $1,000,000 and $60,000 needs $1,500,000. FIRE stands for financial independence, retire early.
The calculator above starts from a 30-year-old spending $50,000 a year, with $50,000 invested and $30,000 a year going in. Their FIRE number is $1,250,000, reached at 53 at a steady 4% return, or at 48 if returns match the S&P 500's history.
How much do I need to retire early?
Most early retirees aim for 25 to 33 times their yearly spending: 25 times at a 4% withdrawal rate, about 28.6 times at 3.5% and 33 times at 3%. For $40,000 a year, that's $1,000,000 to $1,333,000. The 4% rule was tested over 30-year retirements; for longer ones, Early Retirement Now's research found 3.5% safer, and Fidelity suggests 3% for retiring before 62.
| Yearly spending | At 4% (25×) | At 3.5% (28.6×) | At 3% (33.3×) |
|---|---|---|---|
| $30,000 | $750,000 | $857,143 | $1,000,000 |
| $40,000 | $1,000,000 | $1,142,857 | $1,333,333 |
| $50,000 | $1,250,000 | $1,428,571 | $1,666,667 |
| $60,000 | $1,500,000 | $1,714,286 | $2,000,000 |
| $80,000 | $2,000,000 | $2,285,714 | $2,666,667 |
| $100,000 | $2,500,000 | $2,857,143 | $3,333,333 |
| $150,000 | $3,750,000 | $4,285,714 | $5,000,000 |
Which rate to plan around depends on how long your money has to last. Retiring at 40 can mean 50 years or more of withdrawals, far longer than the 30 years the 4% rule was built for. Early Retirement Now's safe withdrawal rate research found 3.5% held up much better over 60 years, and Fidelity suggests saving 33 times your expenses, a 3% rate, to retire before 62. Spending a little less after bad market years makes any of these safer.
How does my savings rate change when I can retire?
Starting from nothing, saving 10% of your take-home pay takes about 58 years to reach financial independence at a 4% return after inflation, 50% takes about 18 years, and 70% about 9. A higher savings rate works twice: more money goes in, and you're living on less, so there's less spending to replace. How much you earn doesn't change the years; the share you save does.
| Savings rate | Steady (4%) | S&P 500 (6.8%) |
|---|---|---|
| 5% | 76 years | 52.9 years |
| 10% | 58.3 years | 42 years |
| 15% | 48 years | 35.6 years |
| 20% | 40.8 years | 30.8 years |
| 25% | 35.1 years | 27.2 years |
| 30% | 30.4 years | 24 years |
| 40% | 23.2 years | 19 years |
| 50% | 17.5 years | 14.8 years |
| 60% | 12.9 years | 11.3 years |
| 70% | 9 years | 8.2 years |
| 80% | 5.7 years | 5.3 years |
The savings rate here is the share of take-home pay you invest, with the rest spent, so it works the same on any income. The idea was popularized by Mr. Money Mustache's “shockingly simple math” post in 2012, which assumed a 5% return after inflation; the table uses this calculator's steady and S&P 500 returns instead.
What is Coast FIRE?
Coast FIRE means you've invested enough that, without adding another dollar, growth alone carries it to your FIRE number by a traditional retirement age such as 65. At a 4% return after inflation, a 30-year-old needs about $253,000 invested to coast to $1,000,000 by 65; at the S&P 500's 6.8% average, about $100,000. You still work to cover today's spending, but you no longer need to save for retirement.
| Your age | Steady (4%) | S&P 500 (6.8%) |
|---|---|---|
| 25 | $208,000 | $72,000 |
| 30 | $253,000 | $100,000 |
| 35 | $308,000 | $139,000 |
| 40 | $375,000 | $193,000 |
| 45 | $456,000 | $268,000 |
| 50 | $555,000 | $373,000 |
| 55 | $676,000 | $518,000 |
Coast FIRE suits people who want to downshift: take a lower-paid job they enjoy, work part time or take a long break, while their retirement keeps growing untouched. The catch is that it leans on future returns. If markets do worse than you assumed, coasting gets you less, so it pays to check your Coast FIRE number at the steady return rather than the optimistic one. The calculator does.
What are Lean FIRE and Fat FIRE?
Lean FIRE is financial independence on a modest budget, often about $40,000 a year or less, which needs about $1,000,000 at a 4% withdrawal rate. Fat FIRE is a more comfortable early retirement on $100,000 a year or more, which needs at least $2,500,000. The lines are conventions rather than official definitions.
| Kind | What it means | FIRE number |
|---|---|---|
| Lean FIRE | Living on about $40,000 a year or less | $1,000,000 or less |
| FIRE | Spending between $40,000 and $100,000 a year | $1,000,000 to $2,500,000 |
| Fat FIRE | Living on $100,000 a year or more | $2,500,000 or more |
| Coast FIRE | Enough invested to grow to your FIRE number by 65; work covers today's spending | Less, depending on age |
| Barista FIRE | Enough to partly retire; part-time work covers the gap and may bring health coverage | Less, depending on pay |
The dollar lines follow The Motley Fool's guide to the kinds of FIRE. Fidelity describes Fat FIRE savers aiming to put away closer to 70% of their income, against about 50% for regular FIRE.
How the calculator works
- Your FIRE number is your yearly spending divided by your withdrawal rate. Lean and Fat FIRE use $40,000 and $100,000 a year at the same rate.
- Your investments compound monthly at a yearly return after inflation: 4% steady and 6.8% optimistic, the S&P 500's average with dividends reinvested since 1957. You can change both under “Return assumptions”.
- Your yearly savings go in a twelfth at a time, at the end of each month, and rise with inflation. The FIRE age is the first month your investments reach your FIRE number.
- Your Coast FIRE number is your FIRE number discounted back from 65 at the steady return. You reach it in the first month that stopping saving still gets you to your FIRE number by 65.
- Your savings rate is what you save over what you spend plus what you save. The savings rate table holds that take-home pay and what you've invested where they are.