Calculate your FIRE number, early retirement timeline, and freedom number with savings rate modeling, coast FIRE projections, and lean vs fat FIRE scenarios.
Use the free FIRE Calculator now at tools.bullrunforever.com/freedom-number — no sign-up required.
- FIRE number calculation — find the exact investment portfolio size you need to retire early
- 4% rule analysis — model safe withdrawal rates based on the Trinity Study to ensure your money lasts
- Early retirement timeline — see exactly when you can reach financial independence at your current savings rate
- Savings rate impact modeling — visualize how increasing your savings rate by 5%, 10%, or 20% accelerates your FIRE date
- Coast FIRE projection — find out when you can stop saving and let compound growth carry you to retirement
- Lean vs Fat FIRE scenarios — compare minimal-lifestyle FIRE ($40k/year) against comfortable FIRE ($100k+/year)
Your FIRE number is the amount of money you need invested to live off your portfolio indefinitely. It's typically calculated as your annual expenses multiplied by 25 (based on the 4% safe withdrawal rate). The FIRE Calculator computes this based on your actual spending.
The 4% rule states that you can withdraw 4% of your portfolio in year one of retirement, then adjust for inflation each year, and your money should last 30+ years. It's based on historical stock and bond returns. The FIRE Calculator uses this as the baseline for your freedom number.
Coast FIRE is the point where your existing investments will grow to your full FIRE number by traditional retirement age (65) without any additional contributions. Once you reach Coast FIRE, you only need to earn enough to cover current expenses.
Savings rate is the single most important factor in reaching FIRE. At a 10% savings rate, retirement takes ~40 years. At 50%, it takes ~17 years. At 70%, it takes ~8 years. The FIRE Calculator shows you this relationship with your actual numbers.
This calculator is part of the BullRun Forever Toolkit — 16 free financial calculators including:
This tool is for educational and informational purposes only. It does not constitute financial, tax, or investment advice. Past market performance does not guarantee future results. Consult a qualified financial advisor before making retirement planning decisions. BullRun Forever is not a registered investment advisor.
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