FIRE Calculator
Find the savings you need to cover your spending, and how many years it takes to get there at your current saving rate. It runs in your browser.
Also searched as: financial independence calculator · retire early calculator · fi number calculator · 4 percent rule calculator
Updated November 9, 2026
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How to use it
- 1
Enter your yearly spending
Type what you expect to spend each year in retirement.
- 2
Add your savings
Enter what you have invested and what you save each year.
- 3
Read your FI number and timeline
See the savings you need and how long it takes to reach them.
Questions about fire calculator
What is a FI number?
The savings you need so that a set share each year, the withdrawal rate, covers your spending. It is your yearly spending divided by that rate.
What is the 4% rule?
A rule of thumb that you can withdraw 4% of your savings in the first year and adjust for inflation after, based on past US returns. It is not a guarantee.
Should I enter a return before or after inflation?
After inflation, so the target and the result stay in the money of today.
The FI number
Your FI number is your yearly spending divided by the withdrawal rate you plan to live on. At 4%, spending of 40,000 a year needs 1,000,000.00. A lower withdrawal rate is safer but needs more savings, as the table shows. The time column uses 100,000 saved, 30,000 added each year and a 5% return after inflation.
| Withdrawal rate | Savings needed | Time to get there |
|---|---|---|
| 3% | 1,333,333 | 20 years 5 months |
| 3.5% | 1,142,857 | 18 years 4 months |
| 4% | 1,000,000 | 16 years 7 months |
| 4.5% | 888,889 | 15 years 2 months |
| 5% | 800,000 | 13 years 11 months |
Getting there, and the limits
With those numbers the tool shows 16 years 7 months to reach 1,000,000. Saving 40,000 a year instead of 30,000 shortens it to 13 years 11 months, so the amount you save each year has a large effect on the timeline.
Enter a return after inflation so the target and the result stay in the money of today. The 4% figure is a rule of thumb based on past US returns over about 30 years, and a longer retirement may need a lower rate. Taxes, healthcare costs and the order in which good and bad years arrive are not modelled.