How do I calculate my FIRE number?
Divide your yearly spending by your withdrawal rate. At 4%, that's the same as multiplying by 25, so $50,000 of spending needs $1,250,000. FIRE stands for financial independence, retire early. This tool works in today's dollars throughout, which is why you enter a real return, meaning a return after inflation.
FIRE number = (yearly spending − other income) ÷ withdrawal rate| Yearly spending | 3% | 3.5% | 4% | 4.5% | 5% |
|---|---|---|---|---|---|
| $30,000 | $1,000,000 | $857,143 | $750,000 | $666,667 | $600,000 |
| $40,000 | $1,333,333 | $1,142,857 | $1,000,000 | $888,889 | $800,000 |
| $50,000 | $1,666,667 | $1,428,571 | $1,250,000 | $1,111,111 | $1,000,000 |
| $60,000 | $2,000,000 | $1,714,286 | $1,500,000 | $1,333,333 | $1,200,000 |
| $80,000 | $2,666,667 | $2,285,714 | $2,000,000 | $1,777,778 | $1,600,000 |
| $100,000 | $3,333,333 | $2,857,143 | $2,500,000 | $2,222,222 | $2,000,000 |
For a couple, use your household's spending, income, and savings. Kids and a mortgage belong in your spending figure, though a mortgage ends and kids leave, so your later spending may differ from today's. Income you'd keep, such as part-time work or a pension, lowers the number directly. Keeping $15,000 a year of it takes this example from $1,250,000 to $875,000.
How long does it take to reach financial independence at my savings rate?
Your savings rate matters more than your income, because it works on both ends. Spending less cuts the number you need and raises what you save. Starting from zero at a 5% real return and a 4% withdrawal rate, saving 20% takes about 36.4 years. Saving 50% takes about 16.4.
| Savings rate | Yearly spending | FIRE number | Years to reach it |
|---|---|---|---|
| 10% | $90,000 | $2,250,000 | 51.0 |
| 20% | $80,000 | $2,000,000 | 36.4 |
| 30% | $70,000 | $1,750,000 | 27.7 |
| 40% | $60,000 | $1,500,000 | 21.4 |
| 50% | $50,000 | $1,250,000 | 16.4 |
| 60% | $40,000 | $1,000,000 | 12.3 |
| 70% | $30,000 | $750,000 | 8.7 |
What are Coast FIRE, lean FIRE, and fat FIRE?
Coast FI is the amount that reaches your number by a later age with no more saving, as long as work covers your bills until then. At 35, with $1,250,000 as the goal at 65 and a 5% real return, that's $289,222 today. It's a milestone, and it doesn't mean you can stop working.
| Your age | 4% real | 5% real | 6% real |
|---|---|---|---|
| 25 | $260,361 | $177,557 | $121,528 |
| 30 | $316,769 | $226,613 | $162,632 |
| 35 | $385,398 | $289,222 | $217,638 |
| 40 | $468,896 | $369,128 | $291,248 |
| 45 | $570,484 | $471,112 | $389,756 |
| 50 | $694,081 | $601,271 | $521,581 |
| 55 | $844,455 | $767,392 | $697,993 |
Lean and fat FIRE are informal community terms with no official definition, so the tool lets you set them. With 70% and 150% of your spending as examples, keeping savings level, lean needs $875,000 and takes about 9.9 years, and fat needs $1,875,000 and takes about 18.6.
Is the 4% rule safe for early retirement?
It's less certain than it sounds, because it comes from history over shorter retirements. The figure traces to William Bengen's 1994 study of US stock and Treasury returns. With half stocks and half intermediate-term Treasuries, and raises for inflation each year, 4% never ran out in under 33 years. At 4.25%, a portfolio could run out in as little as 28 years. Up to about 3.5%, it lasted at least 50 years. Bengen counseled no more than 4% in the early years, especially for anyone retiring at 60 or younger.
That's a record of what happened in the US, not a promise. Retiring at 40 can ask your money to last 50 years or more. To show how much the horizon matters, this tool runs a simulation with 5% average real returns and 12% yearly swings. Both are assumptions.
| Withdrawal rate | FIRE number | 30 years | 40 years | 50 years |
|---|---|---|---|---|
| 3% | $1,666,667 | 98% | 94% | 89% |
| 3.5% | $1,428,571 | 94% | 86% | 80% |
| 4% | $1,250,000 | 88% | 75% | 68% |
| 4.5% | $1,111,111 | 79% | 65% | 57% |
| 5% | $1,000,000 | 68% | 54% | 47% |
On a steady 5% return, a 4% withdrawal never runs out. The model's paths can, for a simple reason: returns that swing compound at less than their average. A 5% average with 12% swings compounds at about 4.3% in this model. Bad years early in retirement also hurt more, since you're withdrawing while the balance is down.
What does a FIRE calculator leave out?
- Getting at your money. Withdrawals from a traditional IRA before 59½ can draw a 10% additional tax unless an exception applies, such as a series of substantially equal payments. If most of your money is in pre-tax accounts, reaching your number doesn't mean you can spend it. A Roth conversion is one tool people look at, with its own 5-year rules.
- Tax. The number has no tax in it unless you add a rate. At an average 15%, the example rises from $1,250,000 to $1,470,588, because you need to withdraw more to keep $50,000.
- Health insurance. Medicare usually starts at 65. Coverage before then belongs in your spending, and this tool has no separate line for it.
- Social Security. Enter it under the advanced options and the simulation counts it, though the number doesn't. Take the figure from your statement, and compare claiming ages with our Social Security calculator.
- Real life. The tool assumes steady savings and spending. Your spending may not stay flat over a long retirement.
For a fuller plan with a retirement date, try the retirement calculator, and test a drawdown with the retirement withdrawal calculator. A fee-only financial planner can check a plan like this against your accounts and taxes.
Common questions
What is a FIRE calculator?
It estimates how much you need to stop depending on a paycheck, and when you'd get there, based on your spending, savings, and investment return. FIRE stands for financial independence, retire early.
Does this calculator include inflation?
Yes, by working in today's dollars. You enter a real return, which is your return after inflation, so your number and balance are all in today's buying power. Don't enter a nominal return, or the date will look too soon.
What is the Monte Carlo model doing?
It runs 500 random market paths with your average return and yearly swings, then counts how many last. The seed is fixed, so the same inputs give the same result. It's a statistical model, and real markets can do things it doesn't include.
Should I count my home or rental property?
Count what can fund spending. A home you live in doesn't produce income unless you sell or borrow against it. Enter net rent as income you'd keep, which lowers your number, and leave the property out of your balance so you don't count it twice.
What withdrawal rate should I use?
That's your call. The tool shows your number at rates from 3% to 5%, so you can see the trade: a lower rate takes more years to reach but has left more margin in both history and the model. A longer retirement is a reason to look at the lower end.
Sources
- Determining Withdrawal Rates Using Historical Data (William P. Bengen, 1994, reprinted 2004) · Journal of Financial Planning
- Publication 590-B: Distributions from Individual Retirement Arrangements · Internal Revenue Service
- Medicare costs · Centers for Medicare & Medicaid Services