FIRE Calculators

What is FIRE, in 30 seconds

FIRE — Financial Independence, Retire Early — is a strategy of aggressively saving and investing so your portfolio can cover your living expenses indefinitely. The arithmetic is unforgiving but liberating: if you can live on 4%^[1] of your portfolio each year (the Trinity-Study safe withdrawal rate), then 25× your annual expenses is your FIRE number. Spend $40,000/yr → you need $1,000,000 invested. Spend $80,000/yr → you need $2,000,000.

Once you have a number, the only two levers that matter are your savings rate and real investment return^[2]. At a 25% savings rate FIRE takes about 32 years; at 50% it drops to ~17 years; at 65% it's ~10.5 years.

The four FIRE flavors

• Lean FIRE — minimal lifestyle, ~$25–35k/yr expenses, smallest target. Compare Lean vs Fat vs Barista FIRE.
• Regular FIRE — covers your current lifestyle, ~$40–60k/yr.
• Fat FIRE — richer lifestyle, $100k+/yr.
• Barista FIRE — downshift to part-time work that covers expenses while your portfolio coasts. Often paired with Coast FIRE.

Where to start

1. 1. Find your FIRE number — make the target concrete.
2. 2. Track your progress — turn the number into a dashboard you bookmark and revisit monthly.
3. 3. Check if you've hit Coast FIRE — the moment compound growth alone can finish the job.
4. 4. Stress-test your drawdown — make sure your portfolio survives 30+ years of withdrawals.

FIRE FAQ

Common questions about FIRE, the 4% rule, Coast FIRE and the calculators in this toolkit.

• What is FIRE?

  FIRE (Financial Independence, Retire Early) is a strategy of aggressively saving and investing so that your portfolio can cover your living expenses indefinitely, freeing you from needing a paycheck. The classic rule of thumb: 25× your annual expenses invested in a diversified portfolio.

• What's the difference between Lean, Regular, Fat and Barista FIRE?

  Lean FIRE targets a minimal lifestyle (~$25–35k/yr), Regular FIRE covers your current spending (~$40–60k/yr), Fat FIRE funds a richer lifestyle ($100k+/yr), and Barista FIRE bridges the gap with part-time income so you can downshift sooner. Use the Lean vs Fat vs Barista FIRE Calculator to compare them side by side.

• How do I calculate my FIRE number?

  Multiply your expected annual expenses in retirement by 25 (the inverse of the 4% safe withdrawal rate). $40,000/yr in expenses → $1,000,000 FIRE number. Open the FIRE Number Calculator to model this with your actual numbers.

• What is Coast FIRE?

  Coast FIRE is the point at which your invested portfolio is large enough that compound growth alone — with no further contributions — will reach your full FIRE number by retirement age. After Coast FIRE you can stop investing and just cover your monthly expenses.

• Which FIRE calculator should I start with?

  Start with the FIRE Number Calculator to set a target, then open the FIRE Progress Calculator to turn it into a dashboard you revisit monthly. If you already know your number, jump straight to Coast FIRE or compare flavors with the Lean vs Fat vs Barista FIRE Calculator.

• How fast can I reach FIRE?

  It depends almost entirely on your savings rate. At 25% savings, FIRE takes ~32 years. At 50% savings, ~17 years. At 65% savings, ~10.5 years. The FIRE Progress Calculator shows your savings-rate band live and how it changes your timeline.

• Is the 4% rule still safe?

  The 4% rule comes from the Trinity Study and has held up across most historical 30-year periods. For longer horizons (40+ years) or richer lifestyles, many planners use 3.25–3.5% instead. Stress-test your number with the Retirement Withdrawal Calculator.