FIRE Calculator
Calculate your FIRE number, years to financial independence, and Coast FI target. Supports Lean FIRE, Fat FIRE, and safe withdrawal rate analysis.
FI Number (25× Expenses)
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Years to Financial Independence —
Progress to FI —
Annual Savings Needed —
Extended More scenarios, charts & detailed breakdown ▾
FI Number
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Years to FI —
Annual Savings —
Professional Full parameters & maximum detail ▾
FI Targets
FI Number (SWR-based) —
Inflation-Adjusted FI Number —
SS-Adjusted Annual Need —
Timeline
Years to FI —
Cost Factors
Healthcare Bridge Fund Needed —
Savings Milestones
25% Milestone —
50% Milestone —
75% Milestone —
How to Use This Calculator
- Enter your annual expenses, savings rate, current savings, and expected return to instantly see your FI number and years to FIRE.
- Use the Years to FI tab to model from gross income and savings rate.
- Use the Coast FI tab to find the point where you can stop contributing and still hit your FI number by retirement age.
- Use the Lean vs Fat FIRE tab to compare different retirement spending levels side by side.
- The Professional tier lets you adjust the safe withdrawal rate, account for Social Security, inflation, and pre-Medicare healthcare costs.
Formula
FI Number = Annual Expenses ÷ Safe Withdrawal Rate (e.g., $50,000 ÷ 0.04 = $1,250,000)
Coast FI = FI Number ÷ (1 + Return)^Years to Retirement
Years to FI = iterative compound growth calculation
Coast FI = FI Number ÷ (1 + Return)^Years to Retirement
Years to FI = iterative compound growth calculation
Example
Example: $50,000 annual expenses, 30% savings rate, $50,000 current savings, 7% return. FI Number = $1,250,000. With $24,000/year savings, years to FI ≈ 22 years. Coast FI at age 30 targeting retirement at 65 = $50,000 / 1.07^35 ≈ $114,000.
Frequently Asked Questions
- Your FIRE number is the investment portfolio size that allows you to retire. The standard formula is Annual Expenses × 25, which corresponds to a 4% safe withdrawal rate from the Trinity Study.
- The safe withdrawal rate (SWR) is the percentage of your portfolio you can withdraw each year without running out of money. The classic 4% rule is based on a 30-year retirement horizon. More conservative retirees use 3–3.5% for longer retirements.
- Coast FI is the point at which your current savings will grow to your full FI number by traditional retirement age (65) without any additional contributions — you can "coast" from that point.
- Lean FIRE means retiring on a frugal budget (often under $40K/year), while Fat FIRE means retiring with a more lavish lifestyle (often $80K–$120K+/year). The key difference is your target annual expenses and therefore your required FI number.
- Yes. If you expect Social Security benefits, your portfolio only needs to fund the gap between your expenses and your SS income. The Professional tier lets you enter your expected SS benefit to reduce your required FI number.
Related Calculators
Sources & References (5) ▾
- SEC Investor.gov — Retirement Planning Tools — U.S. Securities and Exchange Commission
- SSA — Early Retirement and Reduced Benefits — Social Security Administration
- IRS — Early Retirement Distributions and Penalties (Topic 558) — Internal Revenue Service
- FINRA — Retirement Planning Fundamentals — Financial Industry Regulatory Authority
- Department of Labor — Retirement Savings Basics — U.S. Department of Labor