Calculate your FIRE target number, Lean/Fat tiers, Coast metrics, and years to retirement.
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Enter your current age, existing investments, and annual household savings.
Specify desired annual living expenses and assumed investment growth rate (e.g. 7%).
View your Lean, Standard, and Fat FIRE targets alongside your exact retirement timeline.
The 4% rule (from the Trinity Study) states that you can safely withdraw 4% of your investment portfolio annually, adjusted for inflation, with a high probability of never depleting principal over 30+ years.
Lean FIRE covers basic essential living expenses (typically 75% of average budget), while Fat FIRE accommodates an abundant lifestyle with luxury travel and higher discretionary spending.
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