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FIRE Calculator

How many years until financial independence? Calculate your FIRE number using the 25x rule and see exactly how long it'll take at your current savings rate.

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Your total monthly spending in retirement

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$
%

Historical S&P 500 avg ~7% real

Progress to FIRE number ($1,200,000)7%

FIRE number

$1,200,000

Time to FIRE

18y 7m

4% annual withdrawal

$48,000

What you can spend per year

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What is FIRE and how does the 25x rule work?

FIRE stands for Financial Independence, Retire Early. The core idea: accumulate enough invested assets that your portfolio's returns can cover your living expenses indefinitely — and you never need to work again unless you choose to.

The 25x rule comes from the Trinity Study (1998), which found that a portfolio could sustainably withdraw 4% annually with a very high success rate across 30-year periods. Working backwards: if you need $50,000/year, you need $50,000 × 25 = $1,250,000 invested. That's your FIRE number.

The 4% rule caveats

The 4% rule was designed for 30-year retirements. If you're retiring at 40 with a 50-year horizon, many FIRE followers use 3–3.5% to be safer. Fat FIRE (higher expenses), Lean FIRE (frugal), and Coast FIRE (stop contributing and let it grow) are common variations.

The fastest lever to pull

Your savings rate is the biggest variable. Someone saving 10% of income may take 40+ years to reach FIRE. Someone saving 50% can often reach it in 15–17 years. Reducing expenses does double duty: it lowers your FIRE number AND increases your savings rate simultaneously.