Free Financial Tool
FIRE Calculator
Find your FIRE number, years to financial independence, and compare all four FIRE variants — Lean, Regular, Fat, and Coast FIRE.
Your FIRE Number
—
Years to FIRE
—
FIRE Age
—
Progress
—
Savings Rate
—
Monthly Passive Income at FIRE
—
Gap to FIRE Number
—
FIRE Variants Comparison
Path to FIRE — Balance vs. FIRE Target
How the FIRE Calculator Works
FIRE (Financial Independence, Retire Early) is achieved when your portfolio generates enough passive income to cover your expenses indefinitely.
FIRE Number = Annual Spending / (SWR / 100)
// Years to FIRE (iterate, cap at 100):
balance = balance × (1 + return) + annual_savings
stop when balance ≥ FIRE Number
// Coast FIRE Number:
CoastFIRE = FIRENumber / (1 + return)^years_to_retirement
Worked Example
Age 30, save $2,000/month, $50,000 savings, 7% return, $60,000 annual spending, 4% SWR:
- FIRE number: $1,500,000
- Years to FIRE: ≈ 22 years (retire at 52)
- Monthly passive income at FIRE: $5,000/month
- Current savings rate: 24% of $100K income
Frequently Asked Questions
What is the FIRE number?▾
Your FIRE number is the portfolio size needed to sustain withdrawals indefinitely. Formula: FIRE Number = Annual Spending / Safe Withdrawal Rate. At 4% SWR and $60,000/year spending, your FIRE number is $1,500,000. At 3% SWR (more conservative), it's $2,000,000.
What are the FIRE variants?▾
Lean FIRE: very frugal lifestyle (<$40K/year spending), 3% SWR. Regular FIRE: 4% SWR, typical retirement spending. Fat FIRE: $100K+ annual spending, 3.5% SWR to sustain a luxurious lifestyle. Coast FIRE: save aggressively until your portfolio can grow to the FIRE number without further contributions.
How do I calculate years to FIRE?▾
Iterate year by year: balance = balance × (1 + return) + annual_savings. Stop when balance ≥ FIRE number. The key variable is your savings rate — higher savings rate dramatically cuts years to FIRE. Going from 20% to 50% savings rate can cut time to FIRE by 15–20 years.
What is a safe withdrawal rate?▾
The percentage of your portfolio you can withdraw in year one (adjusting for inflation annually) with high probability of lasting 30+ years. The classic 4% rule comes from the Trinity Study. For early retirees with 40–50 year horizons, 3–3.5% is more conservative.
What is Coast FIRE?▾
Coast FIRE is the point where your invested assets will grow to your full FIRE number by retirement age — without any additional contributions. Once you hit Coast FIRE, you only need income to cover living expenses, not to save. Formula: CoastFIRE = FIRENumber / (1+r)^years_to_retirement.
Related Calculators
Example Scenarios — See the Real Numbers