Financial Independence Calculator
Calculate your FIRE (Financial Independence, Retire Early) number based on annual spending and the 4% rule, and estimate years until work is optional.
FIRE Target & Safe Withdrawal Rate Formulas
FI Target Number = Annual Retirement Spending / (Safe Withdrawal Rate / 100) | Current Progress % = (Current Portfolio / FI Target) × 100- 4% Rule (Trinity Study): Historically, withdrawing 4.0% of your portfolio in Year 1 and adjusting for inflation lasted 30+ years in 95%+ of historical 50-year rolling periods.
- Conservative SWR: Early retirees under age 45 often use 3.25% to 3.50% (requiring 28.5x to 30x annual expenses).
- LeanFIRE vs FatFIRE: LeanFIRE covers bare essentials (~75% target); FatFIRE accommodates abundant luxury (~150% target).
Step-by-Step Worked Example
Calculation Steps:
How to Use This Calculator
Assumptions & Limitations
- Assumes a globally diversified portfolio of low-cost index equities and fixed income yielding real (inflation-adjusted) historical growth.
Frequently Asked Questions
What is the 4% rule in financial independence?
Derived from the famous Trinity Study, the 4% rule states that you can withdraw 4% of your initial portfolio value in your first year of retirement, adjust that dollar amount for inflation each year, and have minimal risk of running out of money over a 30-year span.
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