FIRE stands for Financial Independence, Retire Early. This calculator shows the age you can retire early and whether your money lasts to age 100.
Change any input and the result, chart and table update right away.

The 4% rule
The 4% rule says that if you withdraw 4% of your savings in the first year of retirement, and then the same amount adjusted for inflation each year, your money is likely to last 30 years.
Put another way, you can retire once you have 25 times your annual spending (1 ÷ 4%). It assumes you spend some of the principal, not only the returns.
This calculator shows annual spending ÷ withdrawal rate as your "FIRE number". You can choose a withdrawal rate from 3% to 5% (4% by default).
The withdrawal rate is the share of your savings you spend each year. A lower rate is more cautious and needs more savings: with $40,000 a year of spending, you need $1 million at 4% and about $1.33 million at 3%.

Choosing a withdrawal rate
・The 4% rule comes from William Bengen's 1994 study of 30-year retirements with US stocks and bonds.
・In his 2025 book "A Richer Retirement", Bengen raised the figure to 4.7% for a more diversified portfolio, and suggested that people retiring now may be able to use 5% or more.
・Morningstar's 2025 research put the safe starting rate at 3.9%, for inflation-adjusted withdrawals with a 90% chance of lasting 30 years.
・These figures assume a 30-year retirement. An early retirement can last 50 years or more, so many people plan for 3% to 3.5%.
・Whatever rate you choose, the "lasts to age 100" result is calculated separately from your expected return and spending.

Assumptions
・Until retirement you invest the monthly contribution every month, with returns compounded monthly.
・In retirement, your annual spending is withdrawn monthly while the rest stays invested. With Social Security or a pension, only spending above the benefit is withdrawn, and any benefit above your spending is added to your savings.
・The expected return is a real return (after inflation), so all amounts are in today's dollars.
・The chart splits your balance into current savings, contributions (money added later) and investment growth. Withdrawals reduce the three in proportion.
・Taxes and fees are not included. Withdrawals from a traditional 401(k) or IRA are taxed as income, so plan for a larger FIRE number if most of your savings are in those accounts.
・The earliest FIRE age is the earliest retirement age at which your money lasts to age 100.

This is a simplified model for planning, not financial advice. Results are estimates and future returns are not guaranteed.

⇒FIREシミュレーター (Japanese)