What it does
FIRE stands for financial independence, retire early. The idea is simple: once your savings can pay for your yearly spending by withdrawing a small share each year, work becomes a choice. This tool turns your spending into that target, called your FIRE number, and tells you how many years it takes at your current saving.
The saving-rate table shows the big lever: the more of your income you save, the less you spend, so you need a smaller pot and you build it faster. For the steps around this, see the compound interest calculator, the savings goal tool for a nearer target, and the retirement planner for a plan to a fixed age.
How to use it
- Pick your currency and enter your income after tax and your spending, both per year.
- Enter what you have saved so far.
- Enter the return you expect after inflation (4 to 5% is a common cautious guess for a mix of shares and bonds).
- Keep the withdrawal rate at 4%, or change it.
- Read the FIRE number, the years to go, the chart and the table.
What each setting does
- Return after inflation: growth minus price rises, so all numbers stay in today’s money.
- Safe withdrawal rate: the share of the pot you take out each year. Lower is safer and needs a bigger pot.
- Saving rate table: the same income saved at 10% up to 70%.
Worked example
You spend 40,000 a year and use a 4% withdrawal rate. Your FIRE number is 40,000 / 0.04 = 1,000,000. With 20,000 saved, 20,000 added each year and a 5% real return, you get there in about 25 years. Saving 30,000 a year instead cuts it to around 19 years.
FAQs
Is 4% safe? It held in most 30-year periods in US history. If you retire at 40, your money must last longer, so many use 3 to 3.5%.
What about pensions or other income? Use the retirement planner, which takes other income into account.
Does this include tax? No. Withdrawals may be taxable where you live. Not financial or tax advice.
Why is my number so big? Spending is multiplied by 25 at 4%. Cutting spending helps twice: you need less, and you save more.
Where the numbers come from
- FIRE number = yearly spending / withdrawal rate. The 4% rule of thumb comes from the 1998 Trinity study of US stocks and bonds over 30-year periods; it is a guide, not a guarantee. Years to target use the standard growth formula with yearly steps.
Standard scientific values, such as constants, atomic weights and melting points, are facts found in every textbook; we name where ours were checked. If you are an author or publisher and want a value, a credit or a table changed or removed, tell us and we will act quickly.
Last updated 2026-11-10.