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FIRE Calculator

Financial Independence, Retire Early — find out when you can reach FI.

Traditional FIRE: 4% (multiply by 25)

Years to Financial Independence

19 years

FI Target: $1,000,000

FI Target

$1,000,000

$40,000 ÷ 4.0%

Monthly Savings Needed

$2,000

$24,000/year

Annual Return

7%

Savings Trajectory

YearTotal Savings% of FI Target
Today$50,0005.0%
Year 4$172,09817.2%
Year 9$379,39537.9%
Year 14$670,13867.0%
Year 18$984,97398.5%
Year 19$1,077,922100.0%
SWR: 4%
FI Multiple: 25x

How This Is Calculated

This FIRE calculator determines your Financial Independence (FI) number and projects how many years it will take to reach it based on your current savings, monthly contributions, and expected investment returns.

FI Number: Your target = annual expenses ÷ safe withdrawal rate (SWR). With the standard 4% SWR, this simplifies to annual expenses × 25. For example, $40,000/year in expenses requires $1,000,000 in savings.

Years to FI: The calculator simulates year-by-year portfolio growth: each year, your savings grow by the expected return rate, plus your annual contributions (monthly savings × 12). The simulation runs until your savings reach the FI target.

The 4% rule (Trinity Study, 1998) found that withdrawing 4% of your portfolio in the first year, then adjusting for inflation each subsequent year, had a ~95% success rate over 30 years with a diversified stock/bond portfolio.

FI Number = Annual Expenses / Safe Withdrawal Rate. 4% rule from the Trinity Study (1998). Uses real (inflation-adjusted) returns. Past performance does not guarantee future results.

Frequently Asked Questions

Is the 4% rule safe for early retirement?

The 4% rule comes from the 1998 Trinity Study, which found that a 4% annual withdrawal rate had a high probability of lasting 30+ years. For early retirees with 40+ year horizons, many planners recommend 3-3.5% to be more conservative.

What is Coast FIRE?

Coast FIRE is when you have enough saved that, without any additional contributions, compound growth alone will grow your portfolio to your full FI number by traditional retirement age (e.g., 65). At that point, you only need to cover current expenses.

What is the FI number?

Your FI number is the savings needed to cover annual expenses indefinitely using the safe withdrawal rate. The common formula is: FI Number = Annual Expenses × 25 (which corresponds to a 4% withdrawal rate).

What is the difference between Lean FIRE and Fat FIRE?

Lean FIRE targets a frugal lifestyle, typically with annual expenses under $40,000-$50,000 and a FI number around $1M-$1.25M. Fat FIRE targets a more comfortable lifestyle with higher spending ($100,000+/year, FI number $2.5M+).

How does inflation affect FIRE calculations?

The 4% rule already accounts for inflation — you increase your withdrawal amount each year by the inflation rate. When using real (inflation-adjusted) returns of 5-7%, the calculation automatically handles inflation.

⚠️ Estimates only. Past investment returns do not guarantee future results. The 4% rule is a guideline, not a guarantee. Consult a financial advisor.