InterestMath

FIRE Calculator

Financial Independence, Retire Early calculator. Calculate your FIRE number, years to FIRE, and explore Coast FIRE and Lean FIRE.

Your Financial Details

FIRE Number

$1,000,000

Years to FIRE

14 years

FIRE Age

Age 44

Savings Rate

50.00%

FIRE Number

$1,000,000

$40,000 / 4%

Years to FIRE

14

Retire at Age

44

Traditional FIRE requires $1,000,000 to cover your full annual expenses of $40,000 using the 4% withdrawal rate.

Savings Growth Toward FIRE
How It Works

The FIRE calculator determines how much you need to save and how long it will take to reach financial independence based on your income, expenses, and investment returns.

FIRE Number = Annual Expenses / Withdrawal Rate

Savings Rate = (Income - Expenses) / Income

Coast FIRE = FIRE Number / (1 + Return Rate)^(Years to 65)

  • Traditional FIRE = Full expenses covered by investments
  • Lean FIRE = 50% of current expenses (more frugal retirement)
  • Coast FIRE = Enough saved that growth alone reaches FIRE number by 65
  • 4% Rule = Withdraw 4% per year with high probability of lasting 30+ years

Each year, your savings grow by your annual savings (income minus expenses) plus investment returns on the existing balance. The calculator projects this growth until you reach your FIRE number.

Frequently Asked Questions

This calculator is for educational purposes only and does not constitute financial advice. Consult a qualified financial advisor for personalized guidance.