Question 1

What is the FIRE number?

Accepted Answer

Your FIRE number is the portfolio size needed to sustain your annual expenses indefinitely through investment withdrawals. It is calculated as Annual Expenses divided by the Safe Withdrawal Rate. For example, with $40,000 annual expenses and a 4% withdrawal rate, your FIRE number is $1,000,000.

Question 2

What is the 4% rule?

Accepted Answer

The 4% rule comes from the Trinity Study, which found that retirees who withdraw 4% of their portfolio in the first year of retirement (adjusting for inflation thereafter) have a very high probability of not running out of money over a 30-year period. It is a widely used guideline but not a guarantee.

Question 3

What is the difference between Lean, Standard, and Fat FIRE?

Accepted Answer

Lean FIRE targets a minimalist lifestyle with reduced expenses. Standard FIRE covers your current lifestyle expenses. Fat FIRE provides for a more comfortable, expanded lifestyle. Each variant calculates a different portfolio target based on the expense level you aim to cover.

Question 4

What is Coast FIRE?

Accepted Answer

Coast FIRE is the point where your existing investments will grow to your FIRE number by traditional retirement age without any additional contributions. Once you reach Coast FIRE, you only need to earn enough to cover current expenses — you no longer need to save for retirement.

Question 5

How does savings rate affect time to FIRE?

Accepted Answer

Savings rate is the single most powerful lever for reaching FIRE. A higher savings rate means you are simultaneously investing more AND proving you can live on less, which lowers your FIRE number. Someone saving 50% of their income will reach FIRE dramatically faster than someone saving 10%.

Question 6

Should I use nominal or inflation-adjusted values?

Accepted Answer

Inflation-adjusted (real) values give you a clearer picture of future purchasing power. Enable the inflation adjustment in advanced settings to see what your portfolio will actually be worth in today's money. This is especially important for long time horizons of 15+ years.

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