FIRE Calculator — Financial Independence, Retire Early
Calculate your FIRE number, see when you can achieve financial independence, and visualize your path to early retirement. Adjust your savings rate, return expectations, and spending to find your timeline.
How This Calculator Works
First the calculator finds your FIRE number — the portfolio size where your chosen withdrawal rate covers your annual expenses. Then it projects your current savings plus monthly contributions forward, compounding monthly at your expected return, until the portfolio crosses that line. The crossing point is your financial independence date.
FIRE number = annual expenses ÷ withdrawal rateAt the default 4% withdrawal rate that works out to annual expenses × 25. The projection then grows your balance by (annual return ÷ 12) each month and adds your monthly contribution.
Assumptions baked into the math
- A constant annual return, compounded monthly.
- A fixed withdrawal rate — the 4% default comes from the Trinity Study; drop it to 3.5% for a more conservative plan.
- Expenses and contributions stay flat. To keep everything in today’s dollars, use a real (after-inflation) return like 7% rather than a nominal 10%.
- Results are pre-tax — what you keep in retirement depends on which account types you’re withdrawing from.
A worked example
Spending $50,000/year at a 4% withdrawal rate gives you a $1,250,000 FIRE number. Starting from $100,000 and investing $2,000/month at a 7% return, you’d cross that line in about 18 and a half years. Cut $10,000 from your annual spending and the target itself drops by $250,000 — spending less pulls the finish line closer AND speeds you up.
Frequently Asked Questions
What is FIRE?
FIRE stands for Financial Independence, Retire Early. It means accumulating enough investments that the returns cover your living expenses indefinitely — so work becomes optional. "Retire" doesn't necessarily mean stop working; it means having the freedom to choose.
How do I calculate my FIRE number?
Your FIRE number is your annual expenses divided by your safe withdrawal rate. At the standard 4% withdrawal rate, multiply your annual expenses by 25. For example, if you spend $50,000/year, your FIRE number is $1,250,000.
What is the 4% rule?
The 4% rule (from the Trinity Study) suggests you can withdraw 4% of your portfolio in year one of retirement, then adjust for inflation each year, with a very high probability of not running out of money over 30 years. Some conservative planners use 3.5% for longer retirements.
What is a realistic rate of return?
The S&P 500 has historically returned about 10% before inflation, or 7% after inflation. For FIRE planning, using 6-7% is conservative and accounts for inflation. If you include bonds or alternatives, adjust accordingly.
How can I reach FIRE faster?
The two biggest levers are increasing your savings rate and reducing your annual expenses. Cutting $10,000 from your annual spending both adds to your investments AND reduces your FIRE number by $250,000 (at a 4% withdrawal rate). Income growth helps too, but only if you don't inflate your lifestyle.