FIRE Calculator
The FIRE Number is your portfolio target for financial independence: annual spending ÷ safe withdrawal rate. At the standard 4% rule, you need 25× your annual expenses. A $50,000/year lifestyle requires a $1.25M portfolio. This calculator computes your exact FIRE number, years to reach it, and supports all four FIRE variants — Lean, Regular, Fat, and Coast FIRE.
How the FIRE Number Is Calculated
Financial Independence is achieved when your investment portfolio generates enough passive income to cover all living expenses indefinitely. The math uses the Safe Withdrawal Rate (SWR) — historically the percentage you can withdraw annually without running out of money over a 30+ year retirement.
| Variable | Definition |
|---|---|
| FIRE Number | Total portfolio balance needed to retire permanently |
| Annual Spending | Total yearly living expenses in retirement (today's dollars) |
| SWR (4%) | Safe Withdrawal Rate — percent you can spend annually with 95%+ success rate |
| 25× Rule | Shorthand for 4% SWR: FIRE Number = Spending × 25 |
| Savings Rate | % of income saved — single biggest lever for time to FIRE |
Worked example: Annual spending $48,000 ÷ 4% SWR = $1,200,000 FIRE number. If you have $50,000 saved and invest $24,000/year ($2,000/month) at 7% returns, you reach $1.2M in approximately 21 years (FIRE at age 51 from age 30). Increasing your savings rate to $36,000/year cuts that to 17 years.
🔥 FIRE Expert Insight
Your Savings Rate Matters More Than Your Income: Two people earning $100k/year can have wildly different FIRE timelines. Person A saves 10% ($10k/year) and reaches FIRE in ~43 years. Person B saves 50% ($50k/year) and reaches FIRE in ~17 years. The same principle works at $60k income or $300k income — percentage saved is what drives time to financial independence. Most FIRE achievers focus obsessively on lowering the expense side (housing, cars, food) rather than earning more, because spending cuts are permanent while income gains aren't guaranteed. The fastest FIRE path: house hack, drive used cars, skip lifestyle inflation as income rises.
FIRE Calculator FAQ
What is the FIRE number?
Your FIRE number is the total investment portfolio balance you need to retire and never work again. Using the standard 4% rule, your FIRE number = annual spending × 25. If you spend $50,000/year, your FIRE number is $1,250,000.
What's the difference between Lean FIRE, Fat FIRE, and Coast FIRE?
Lean FIRE targets a frugal retirement (under $40k/year). Regular FIRE targets a moderate lifestyle. Fat FIRE targets luxury ($100k+/year). Coast FIRE means you've saved enough that compound growth alone reaches your FIRE number by 65 — you just need to cover current expenses without additional saving.
What savings rate do I need for early retirement?
A 10% savings rate takes ~43 years. A 25% savings rate takes ~32 years. A 50% savings rate takes ~17 years. A 75% savings rate takes ~7 years. The FIRE movement popularized extreme savings rates (40–70%) to achieve retirement in 10–15 years instead of 40.
Is the 4% withdrawal rate still valid in 2026?
The 4% rule (from the 1994 Trinity Study) remains widely used but some FIRE practitioners use 3–3.5% for very long retirements (40–50 years). For a 30-year retirement, 4% is historically safe 95%+ of the time. For a 50-year early retirement, 3.5% is more conservative and prudent.
What are the biggest risks to early retirement?
The top risks are: (1) Sequence-of-returns risk — a crash in your first 1–5 retirement years can be devastating; (2) Healthcare costs before Medicare at 65; (3) Underestimating longevity — plan to 90; (4) Lifestyle inflation as you age. Most FIRE practitioners hold 1–3 years of expenses in cash/bonds to avoid selling equities during downturns.
How is Coast FIRE calculated?
Coast FIRE Number = Full FIRE Number ÷ (1 + annual return)^years until age 65. Example: FIRE number $1M, age 35, 7% returns: Coast FIRE = $1,000,000 ÷ (1.07)^30 ≈ $131,367. If you have $131,367 today, you can stop contributing and just let it grow to $1M by 65.
FIRE Calculator — Financial Independence, Retire Early
Your Numbers
Your FIRE Outlook
Based on your results — what to do next:
Stress-test with the 4% rule
Your FIRE number is $1,200,000. Run the full retirement model to check social security offsets and sequence-of-returns risk.
Visualize your compound growth
Saving $3,500/mo at 7% compounds faster than most people expect. See the exponential curve year by year.
Maximize tax-advantaged accounts
Your savings rate of 46.7% can be boosted by using the full 2026 401(k) limit of $23,500 before taxable accounts.