Understand your money before you invest it
Plain-English guides with no hidden agenda. Written for someone who wants to actually understand the math, not just follow a formula.
What does FIRE stand for?
Four words that redefined what retirement can look like.
Building enough wealth that work becomes optional — not because you hate your job, but because you've bought back the freedom to choose. Financial independence is a number, not a feeling.
Your portfolio covers your living expenses indefinitely. You no longer trade time for money. Independence means the stock market, not your employer, funds your life.
Stepping away from mandatory full-time work — usually decades earlier than the traditional age 65. In the FIRE community, "retire" often means pivoting to meaningful work, not stopping entirely.
Most FIRE practitioners target their 30s, 40s, or early 50s. Early retirement requires aggressive savings rates (50–70%+), low spending, and high-return investments — but it's increasingly achievable on a middle-class income.
What type of FIRE are you?
Six flavors of financial independence — from bare-minimum lean to fully fat. Click any card to deep-link, then use the simulator to run your numbers.
leanFIRE
For the optimizer who values freedom above comfort.
Retire on minimal spending through radical frugality and low fixed costs. Often involves geo-arbitrage, paid-off housing, and keeping needs extremely low. Requires the highest mental discipline of any FIRE variant.
Calculate my number →FIRE
The classic — 4% rule, standard middle-class lifestyle.
The original Trinity Study target range. Live comfortably without austerity. Most FIRE content assumes this range. Achievable on a solid income with 10–15 years of aggressive saving.
Calculate my number →ChubbyFIRE
Comfortable retirement without the fat price tag.
Travel, nice restaurants, premium healthcare — without the extreme luxury of fatFIRE. Growing fast among dual-income tech couples. Requires careful tax planning as portfolio size creates RMD and tax complexity.
Calculate my number →fatFIRE
Retire wealthy, not just financially independent.
Maintain a high lifestyle in retirement — private travel, top-tier healthcare, luxury experiences. Typically reached by high earners or entrepreneurs. Tax optimization is critical at this scale.
Calculate my number →CoastFIRE
Do the hard work early, then coast to the finish.
Reach a portfolio size early enough that compounding alone — with no new contributions — will grow it to your FIRE number by traditional retirement age. Once you hit CoastFIRE, your investments work for you while you work for current expenses.
Calculate my number →BaristaFIRE
Semi-retire and let the portfolio do the heavy lifting.
Work part-time in a low-stress job that covers basic living expenses (health insurance, groceries, utilities). Your investments grow untouched or are drawn down slowly. More flexibility than full FIRE, less grind than full-time work.
Calculate my number →The fundamentals, explained
Eight topics every FIRE practitioner needs to understand. Each guide includes a key takeaway and the most common mistake.
The 4% Rule
The 4% rule comes from a 1994 paper by financial planner William Bengen. He studied historical US stock and bond returns going back to 1926 and asked a simple question: what's the highest withdrawal rate that would have survived every 30-year retirement period in the historical record?
His answer was 4.15% — later rounded to 4% and confirmed by the 1998 Trinity Study, which tested the same idea across a range of stock/bond allocations. The rule means this: in your first year of retirement, withdraw 4% of your portfolio. Every year after, adjust that dollar amount for inflation. Don't recalculate each year based on current portfolio value.
For a $1,000,000 portfolio, that's $40,000 in year one. If inflation is 3%, year two is $41,200. And so on. The portfolio doesn't need to survive forever — the original research tested 30-year windows, matching a typical retirement of age 65 to 95.
Across every 30-year period in US history, a 50/50 or 75/25 stock/bond portfolio using the 4% rule had a success rate above 95%. The failure periods clustered around the late 1960s, when retirees hit both high inflation and poor equity returns simultaneously — a brutal combination.
There are real limits to this rule. It was derived from US data only — the US had an unusually good 20th century. Applied globally, the safe rate drops to about 3.5%. It assumes a static withdrawal — real retirees spend more in early retirement ("go-go years") and less later. And critically, it was designed for 30 years, not 40 or 50. Early retirees in their 40s using 4% face meaningfully higher failure rates.
The 4% rule is a historical guideline, not a guarantee — it survived 95%+ of 30-year periods in backtesting, but some periods failed.
Assuming 4% is safe for 40–50 year retirements. Longer horizons need 3.3–3.5% to maintain similar safety.
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