General
Retirement Calculator (FIRE & 4% Rule)
Find your FI number with the 4% rule, the age your savings reach it, and the yearly income they support at retirement, all in today's money.
Financially independent at age
64
in 34 years
Your FI number
$1,000,000
today's money
Progress
5.0%
of your FI number saved
Savings at 65
$1,068,409
today's money
Income it supports
$42,736
per year, today's money
Return after inflation
3.88%
Money lasts until age
100+
saving until retirement, then spending
To spend $40,000 a year in today's money at a 4.0% withdrawal rate, you need about $1,000,000 invested: your financial independence (FI) number.
Saving $1,000 a month at a 3.88% return after inflation, you would reach it in about 34 years, at age 64.
By age 65 you would have about $1,068,409 in today's money, enough to spend about $42,736 a year at the same withdrawal rate.
Spending $40,000 a year from age 65, your savings would last beyond age 100.
Your numbers
+Advanced options
Savings by age, in today's money
See how the withdrawal rate changes your target
Same savings and spending — three withdrawal rates. A lower rate is more cautious, which matters most for long retirements, but it raises the amount you need.
3% withdrawal rate
$1,333,333
FI at age 70
3.5% withdrawal rate
$1,142,857
FI at age 67
4% withdrawal rate
$1,000,000
FI at age 64
How the projection works
FI number = Yearly spending ÷ Withdrawal rate
At a 4% withdrawal rate, spending 40,000 a year takes 40,000 ÷ 0.04 = 1,000,000 invested. Your savings are then projected month by month in today's money: they grow at the return after inflation, (1 + expected return) ÷ (1 + inflation) − 1, compounded monthly, and your monthly savings are added at the end of each month. The FI age is the first birthday on which the projected savings reach the FI number.
How to set your FI number
Retirement planning starts with one number: how much you need invested for your savings to pay for the life you want. Dividing your yearly spending by a sustainable withdrawal rate turns that question into a target you can track.
Spending matters as much as saving. Every extra amount you plan to spend each year raises the target by 25 times that amount at a 4% withdrawal rate. Cutting planned spending moves the finish line closer from both ends: you need less, and you have more left over to save.
Time and returns do the heavy lifting. Early on, most of the growth comes from what you put in; after a decade or two, returns on the balance usually overtake your contributions. That is why starting early, as the compound interest guide shows, matters more than a slightly higher return.
The projection assumes steady returns and inflation. Real markets swing, and a bad run just after you retire hurts more than the same run later on. Test a cautious return and a lower withdrawal rate alongside your central case, and revisit the plan as your numbers change.
Retirement FAQ
What is the 4% rule?+
It is a rule of thumb from US research in the 1990s (William Bengen's 1994 study, then the "Trinity study"): withdrawing 4% of a stock-and-bond portfolio in the first year of retirement, then raising that amount with inflation, lasted at least 30 years in almost every historical period tested. It is a starting point drawn from past markets, not a guarantee.
The 4% rule explained: where 25 times your spending comes from
What is FIRE?+
FIRE stands for financial independence, retire early. The idea is to save and invest a large share of your income until your portfolio can cover your spending — your FI number — so that working becomes optional, often well before a traditional retirement age.
Why use a lower withdrawal rate for early retirement?+
The 4% rule was tested on 30-year retirements. Someone retiring at 40 may need their savings to last 50 years or more, and a longer horizon leaves more room for a bad sequence of market returns. Many early retirees plan on 3–3.5% for that reason, which raises the FI number.
The 4% rule explained: where 25 times your spending comes from
Why is everything in today's money?+
Because a pound, dollar or euro in 30 years will buy less than it does now. The projection uses the return after inflation and assumes your monthly savings rise with prices, so every figure — your FI number, your savings at retirement and the income they support — is in today's purchasing power and easy to compare with your current budget.
What does the calculator leave out?+
Taxes, pensions and state benefits are not modeled. If a pension or social security will cover part of your spending, enter only the part your savings must pay for. Fund fees are not modeled separately either; lower the expected return by your fees to include them. Returns are assumed steady, which real markets never are.
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Educational tool, not advice. This calculator illustrates a standard formula using the numbers you enter. It does not account for your full financial picture, taxes, or local market conditions, and it is not a recommendation to buy, sell, or hold any asset. Speak with a licensed professional before making investment decisions.
See our full disclaimer and how we calculate.
Last reviewed 2026-10-17 by the Yield Analyst team