FIRE calculator
FIRE — financial independence, retire early — arrives when the portfolio can pay for your spending at a withdrawal rate you trust; that target is the FI number, also called the FIRE number. The years it takes depend far more on the savings rate than on the return, because a higher savings rate both adds more each year and lowers the target. Enter your income after tax and the share you save; the calculator gives the FI number, the years to reach it and the age you would get there.
Arithmetic from your own inputs: no statutory data Runs in your browser — nothing you type is sent to this site's servers or to its analytics No sign-up Methodology and data status
- FI number
- $1,400,000
- Years to FI
- 26.0 years
- Age at FI
- 56.0
- Saved each year
- $24,000
| How it is built | |
|---|---|
| Spending now, and assumed in retirement (income less savings) | $56,000 |
| FI number: spending ÷ 4.00% withdrawal rate (25.0× spending) | $1,400,000 |
| Starting from $50,000, adding $24,000 a year at 5.0% real | 26.0 years |
| Savings rate | Spending | FI number | Years to FI |
|---|---|---|---|
| 10% | $72,000 | $1,800,000 | 45.8 years |
| 20% | $64,000 | $1,600,000 | 33.7 years |
| 30% | $56,000 | $1,400,000 | 26.0 years |
| 40% | $48,000 | $1,200,000 | 20.1 years |
| 50% | $40,000 | $1,000,000 | 15.4 years |
| 60% | $32,000 | $800,000 | 11.4 years |
| 70% | $24,000 | $600,000 | 7.9 years |
Contributions are added at the end of each year and the portfolio earns the real return every year; spending is assumed to stay the same, in today's dollars, after you stop working. The FI number ignores taxes on withdrawals, Social Security and pensions — the withdrawal calculator adds them.
How the years are computed
Spending is income × (1 − savings rate) and is assumed to continue at that level in retirement, so the FI number is spending ÷ withdrawal rate. Each year the savings (income × savings rate) are added at the end of the year and the whole balance grows at the real return. The years to FI solve P(1+r)n + A·((1+r)n − 1)/r = F for n, where P is current savings, A the annual savings, r the real return and F the FI number. With no return it is simply (F − P) ÷ A.
Why the savings rate dominates
Doubling the savings rate from 25% to 50% cuts spending by a third, which cuts the FI number by a third, while the amount saved doubles. Starting from nothing at a 5% real return, that takes the time from about 32 years to about 17 — 52% of it, a little more than half, because the slower saver's larger balance earns more along the way. Moving from 10% to 50% takes it from about 51 years to about 17. The return matters at the margin; the savings rate sets the order of magnitude. Both figures assume no savings to begin with; the table above uses whatever you entered.
What is left out
- Taxes on withdrawals, Social Security and pensions. The withdrawal calculator includes all three for the drawdown phase.
- Changes in income or spending, a mortgage that ends, children, healthcare before Medicare — enter a spending figure that already reflects what retirement will cost.
- Sequence-of-returns risk: a constant real return is a planning average, not a forecast.