FIRE Calculator
Enter your age, spending and savings to see your lean, regular and fat FIRE numbers and when your savings could reach each one. Nothing is uploaded.
Calculate your FIRE number (financial independence, retire early) in any currency (₹ INR by default): spending ÷ safe withdrawal rate, shown in future money and today's money, with lean and fat FIRE targets, the age your savings reach each, the monthly saving needed for a target age, and a year-by-year table.
FIRE number = yearly spending ÷ withdrawal rate, raised by inflation to the date it is reached. Lean is 70% and fat is 150% of your spending. Savings grow monthly at the return you enter. All rates are your own inputs; no tax rules are applied.
Use a dot for decimals (120000.50); commas and spaces are read as thousands separators. Ages are whole numbers. Percentages are typed as percentages: 4 means 4%. The return is before inflation. A 4% withdrawal rate = 25× spending; 3–3.5% (≈ 28–33×) is a common more cautious rate in India. Lean = 70%, fat = 150% of spending.
This is an estimate from your inputs: returns are not guaranteed and taxes are not included.
Year by year
One row per birthday against the regular target, until the first birthday on or after it is reached, or age 100. Savings can cross the target between birthdays, so the last row may not show savings above it.
| Age | Savings | Regular target |
|---|
How to use the FIRE Calculator
- Enter your current age, what you spend (per year or per month), your invested savings and what you save each month.
- Check the assumptions: inflation, the return before inflation, the withdrawal rate and any yearly increase in your saving. Pick your currency.
- Read the lean, regular and fat targets, each in future money and today's money, with when your savings reach it.
- Add a target age if you have one to see the monthly saving that gets you to the regular target by then, and open Year by year for the full table.
Frequently asked questions
How is the FIRE number worked out?
Your yearly spending today ÷ the withdrawal rate gives the number in today's money. At 4% that is 25× spending. The same figure raised by inflation up to the date you reach it is the number in future money. Lean uses 70% of your spending and fat uses 150%.
How is the date worked out?
Savings grow month by month at the monthly equivalent of the yearly return, your monthly saving is added at the end of each month, and each target rises with inflation each month. The first month your savings are at or above a target is when that target is reached. If that never happens, the page says not reached by age 100.
Is the return before or after inflation?
Before inflation. Enter the return you expect in plain terms, such as 10%, and the inflation rate separately. The calculator raises the target with inflation, so do not take inflation off the return as well.
Which withdrawal rate should I use?
4% = 25× spending is the usual starting point. 3–3.5% (about 28–33× spending) is a common more cautious rate in India. A lower rate gives a larger target. It is your choice, so try a few.
How is the monthly saving for a target age worked out?
It is the monthly saving, starting now and with your yearly increase applied, that brings savings up to the regular target at exactly your target age. It is rounded up to a whole amount. If your savings would get there with no more saving, the page says so.
Are taxes included?
No. No tax rules for any country are applied, and returns are not guaranteed. The result is an estimate from your inputs, not financial advice.
How do I type amounts like 1,20,000 or 120,000.50?
Both work. Use a dot for decimals (120000.50); commas and spaces are read as thousands separators. That means 1.234,56 written the European way is not read correctly, so type 1234.56 instead. Ages are whole numbers only.
Is anything I type sent anywhere?
No. Everything is calculated in your browser. Only your currency and the four assumption rates are remembered, in this browser; Clear removes them. Your age, spending, savings and monthly saving are not stored.
Fun facts about FIRE
- The 4% figure comes from William Bengen's 1994 study of US retirements, which looked for a rate that lasted through the worst historical periods.
- The FIRE movement is often traced to the 1992 book Your Money or Your Life by Vicki Robin and Joe Dominguez.
- By the rule of 72, prices double about every 12 years at 6% inflation, so a target in today's money is about twice as large in future money 12 years on.
- Moving the withdrawal rate from 4% to 3% raises the target by a third, from 25× to about 33× spending.