FIRE Retirement Age Calculator
Calculate your FIRE number and retirement age. Find out exactly when you can achieve financial independence based on your savings rate, expenses, and investment returns.
Your FIRE Number
$1.00M
Annual Expenses: $40,000/yr, 4% Safe Withdrawal Rate
Your FIRE Age
44
14 Years to FIRE
Years
14
Years until FIRE
Annual Income (after tax)
$80,000
Savings Rate: 50% = $40,000/yr
How to Calculate Your FIRE Number and Retirement Age
The FIRE (Financial Independence, Retire Early) movement centers on one key question: "When can I stop working?" The answer depends on your FIRE number — the total amount you need invested to cover your living expenses indefinitely. The formula is simple: FIRE Number = Annual Expenses × 25 (based on the 4% rule from the Trinity Study). But your actual retirement age depends on your savings rate. Someone saving 50% of their income can retire in about 17 years, while someone saving 15% may need 40+ years. Our free FIRE age calculator above crunches these numbers instantly — just adjust the sliders to match your situation and see your personalized FIRE timeline.
How to Use This FIRE Age Calculator
- Current Age — Your age today. The earlier you start planning for FIRE, the sooner you'll reach it.
- Annual Income — Your after-tax income. This determines how much you can potentially save each year.
- Annual Expenses — Your current yearly spending. Lower expenses mean a lower FIRE number AND a higher savings rate.
- Current Savings — How much you've already saved and invested toward your FIRE goal.
- Expected Return — Your assumed annual investment return. 7% is a common conservative estimate (S&P 500 historical average after inflation).
- Safe Withdrawal Rate — Typically 4%, based on the Trinity Study. Lower rates (3-3.5%) are more conservative for longer retirements.
The calculator shows your FIRE number, years until you reach it, your FIRE age, and a progress bar showing how close you are.
Frequently Asked Questions About FIRE and Retirement Age
What is a FIRE number?
Your FIRE number is the total amount of invested assets you need to cover your annual living expenses indefinitely without working. It's calculated as Annual Expenses × 25, based on the 4% safe withdrawal rule. For example, if you spend $40,000/year, your FIRE number is $1,000,000. Once your investment portfolio reaches this amount, you can theoretically withdraw 4% ($40,000) each year adjusted for inflation without depleting your principal.
How does savings rate affect my FIRE age?
Your savings rate is the single biggest factor determining when you can retire. Here's the math: saving 15% of income means ~43 years to FIRE; saving 30% means ~28 years; saving 50% means ~17 years; saving 70% means ~8.5 years. This assumes starting from zero and a 7% real return. The relationship is powerful because a higher savings rate both builds your portfolio faster AND reduces your FIRE number (since you're used to living on less).
What is a safe withdrawal rate for early retirement?
The 4% rule (from the 1998 Trinity Study) is the most common starting point. However, for very early retirement (40+ year horizon), many FIRE practitioners prefer a more conservative 3-3.5% withdrawal rate. The Bengen study originally found that 4% survived 30-year periods in 95% of historical scenarios. Use our 4% Rule Calculator to explore different withdrawal rates and see how they affect your required nest egg.
Does the FIRE age calculation account for inflation?
Yes, if you use an inflation-adjusted (real) return rate. Our calculator uses your Expected Return input — we recommend 7% which is the historical S&P 500 return of ~10% minus ~3% average inflation. This means all projections are in today's dollars, so your FIRE number represents purchasing power equivalent to today. The 4% rule also assumes you increase withdrawals with inflation each year.
I'm 40 with $0 saved — is it too late to FIRE?
No, it's not too late! Even starting at 40, you can achieve FIRE by 55-60 with a high savings rate. For example, saving 60% of a $100,000 income ($60,000/year) at 7% return would get you to a $1M FIRE number in roughly 12 years. Lean FIRE (lower expenses) is also an option — if you can live on $30,000/year, your FIRE number is only $750,000. The best time to start was 20 years ago; the second best time is today.