FIRE Calculator (Retire Early)
See exactly how many years until you can quit your job, based on your savings rate, current investments, and expected returns. The classic "Financial Independence, Retire Early" projection. This free online financial calculator runs entirely in your browser — no signup, no data sent anywhere.
Inputs
Results
Interactive Chart
Drag to pan, scroll to zoom, shift+drag to box-zoom. Combined view of balance, principal paid, interest paid, and total paid.
Amortization Schedule
| Period | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| Click Calculate to generate the schedule. | ||||
How It Works (Formula & Method)
Your target portfolio = annual expenses ÷ withdrawal rate (e.g., $45,000 expenses ÷ 4% = $1.125M). The calculator then solves for how many months of monthly savings, growing at your expected return, are needed to reach that target — starting from your current invested balance. Note that the gap between income and expenses is what matters: someone earning $200k who spends $190k will take much longer than someone earning $80k who spends $40k.
Worked Example
Below is a worked example using the calculator's default values. The same numbers are pre-filled in the form above so you can press Calculate and see the result without typing anything.
Inputs used:
- After-tax Annual Income ($): 80000
- Annual Expenses ($): 45000
- Current Investments ($): 30000
- Expected Annual Return (%): 7
- Safe Withdrawal Rate (%): 4
With these inputs, the calculator computes the metrics shown in the Results panel. Change any value and press Calculate again to see how the result responds — the live widget and the chart both update instantly.
About the FIRE Calculator (Retire Early)
The FIRE movement — short for Financial Independence, Retire Early — is built on a single insight: if you can save enough to support your lifestyle indefinitely from a withdrawal rate of around 4% per year, you are mathematically free to stop working. Your "FIRE number" is the investment portfolio size that makes this possible, traditionally calculated as 25 times your annual expenses.
How to Use This Calculator
Enter your after-tax annual income, what you actually spend in a year (the lower this is, the faster you reach FIRE), your current invested net worth (excluding home equity), your expected investment return, and a withdrawal rate. The default 4% is the classic Trinity Study figure; FIRE skeptics use 3.5% for extra safety, optimists use 4.5%.
Tips & Considerations
- Savings rate is the lever. Going from 15% to 50% savings rate roughly cuts your time-to-FIRE in half.
- FIRE math assumes constant expenses and constant returns. Real life has sequence-of-returns risk — markets can be brutal in the first decade of retirement.
- Variants worth knowing: Lean FIRE (frugal, ~$25k/yr expenses), Fat FIRE ($100k+/yr expenses), Coast FIRE (you have enough invested that compounding alone will get you there by retirement age).
- Healthcare in the U.S. before age 65 is the most underestimated FIRE cost — model it carefully.
Frequently Asked Questions
Is the 4% rule really safe?
It has held up well historically for 30-year retirements. For early retirees facing 50+ year horizons, many planners suggest 3.25–3.5% for extra cushion.
What about Social Security and Medicare?
Most FIRE plans treat these as a bonus — your portfolio should be able to sustain you without them, and any benefits you do receive shorten the period your portfolio needs to last.
Should I include my house?
No — exclude home equity from the FIRE portfolio. You still need somewhere to live in retirement, so it does not generate income.
What return assumption should I use?
For diversified stock/bond portfolios, 7% nominal (or 4-5% real, after inflation) is conservative. Higher numbers may not survive a bad sequence of returns.
Reviewed against: IRS publications, Consumer Financial Protection Bureau (consumerfinance.gov), and current published market data. Results are estimates for educational use only — not financial, tax, or legal advice.