FIRE Calculator

FIRE stands for Financial Independence, Retire Early. It's a movement focused on aggressive saving and investing so you can retire well before the traditional retirement age of 65. The goal is to accumulate enough wealth that investment returns cover your living expenses indefinitely.

Your FIRE number is the total portfolio value you need to retire. It's calculated as: Annual Expenses ÷ Withdrawal Rate. For example, if you spend $40,000/year and use a 4% withdrawal rate, your FIRE number is $1,000,000. Once your portfolio reaches that amount, your withdrawals should sustain you indefinitely.

Your savings rate determines both how much you add to your portfolio each year AND how little you need in retirement (since lower spending means a smaller FIRE number). A high savings rate dramatically shortens your timeline — doubling your savings rate can cut your retirement timeline by a decade or more, whereas a higher investment return alone has a much smaller effect.

The 4% rule originates from the Trinity Study and suggests that withdrawing 4% of your portfolio in the first year of retirement, then adjusting for inflation each year, has historically sustained a portfolio for 30+ years. Many FIRE adherents use 3–3.5% for extra safety given potentially 40–50 year retirements.

No — this calculator focuses on the accumulation phase: how long it takes to reach your FIRE number. It assumes you never draw down the principal and that your investment returns cover your expenses. For post-retirement simulations (running out of money, sequence-of-returns risk), use a dedicated withdrawal phase calculator.

Most FIRE calculators use a real (inflation-adjusted) annual return of 5–7%. A commonly used figure is 5% to be conservative. This accounts for historical stock market returns minus typical inflation. Since your expenses are also in today's dollars, using a real return keeps everything consistent.

This calculator assumes your current annual expenses equal your retirement expenses. If you expect to spend more (travel, healthcare) or less (no mortgage, no kids) in retirement, adjust the Annual Expenses input to reflect your projected retirement spending rather than your current spending.

Yes — FIRE is primarily driven by savings rate, not absolute income. Someone earning $40,000 and saving 50% can reach FIRE in roughly the same number of years as someone earning $200,000 and saving 50%. Keeping expenses low relative to income is the most powerful lever regardless of your income level.