FIRE Calculator

FIRE stands for Financial Independence, Retire Early. The core idea: save and invest aggressively (often 40–70% of income) until your portfolio is 25× your annual expenses — at which point a 4% inflation-adjusted withdrawal can theoretically support you indefinitely.

Multiply your annual expenses by 25 to find your FIRE number. Spend $40,000/year → FIRE number is $1,000,000. Based on the 4% safe withdrawal rate from the Trinity Study. For a more conservative target use 33× (the 3% rule).

Two steps. (1) FIRE number = annual expenses × 25. (2) Years to FIRE: start with your current portfolio, add annual savings (income − expenses) at the start of each year, grow the balance by your assumed real return, repeat until the balance reaches the FIRE number. This calculator runs that loop on every input change.

Savings rate is the single biggest lever. From a zero starting balance at 5% real return: 10% savings → ~51 years to FI · 25% → ~32 yrs · 50% → ~17 yrs · 65% → ~10.5 yrs · 75% → ~7 yrs. Income amplifies the path, but savings rate determines it.

Aggressive FIRE (retire by 35) usually requires very high income or extreme frugality. But the math also works for 'regular FI' — retiring at 50–55 instead of 65. Even halving the gap from 65 buys back 10–15 years of life.

Use a real (after-inflation) return. 5–7% is the standard assumption for a diversified stock-heavy portfolio. The S&P 500 has averaged ~7% real since 1926. Use 5% for conservative planning, 7% for the base case, and re-run at 3% as a stress test.

LeanFIRE = annual spending under ~$40k, very frugal lifestyle. RegularFIRE = $40k–$100k, typical middle class. FatFIRE = $100k+/yr, requires either very high income or 25+ years of aggressive saving. CoastFIRE = save enough early that you can stop contributing and let compounding finish the job by 65.

This calculator works on after-tax cash flows — enter after-tax income and real (after-tax) expected returns. Tax-advantaged accounts (Roth IRA, 401(k)) help on the accumulation side; in withdrawal you'll pay income tax on traditional balances and capital gains on taxable accounts. Plan ~10–15% effective tax in retirement for most US retirees.

FIRE math typically ignores Social Security to be conservative, but for retirement at 62+ it materially reduces the required portfolio. The average benefit is ~$22k/year, which at the 4% rule is equivalent to ~$550k of nest egg. Treat it as a bonus, not a primary plan.

Yes — enter a real (after-inflation) return rate and your numbers stay in today's dollars. If you'd rather use a nominal rate (e.g. 9–10%), then also inflate your expenses each year and project in future dollars; for planning, today-dollar math is much easier.

The biggest threat to early retirement is a big market drop in the first 5–10 years of withdrawals. The same 30-year average return is far less safe if losses hit early. Mitigations: hold 1–3 years of expenses in cash/bonds, lower withdrawal rate to 3.5%, or be willing to cut spending in down years.

Find the portfolio size that, with no further contributions, will grow to your full FIRE number by traditional retirement age. At 7% real, you need to coast for ~10 years to double, ~20 years to quadruple. CoastFIRE lets you down-shift into lower-paid or part-time work while compounding finishes the job.

No. Financial independence and early retirement are separate. FI gives you the option to leave full-time work; many FI folks keep working in roles they enjoy, switch careers, or take sabbaticals. The number on this page is your freedom date, not necessarily your last day of work.

FIRE plans for 40–60 year retirement horizons (vs ~25 years for traditional 65 retirement), so it uses more conservative withdrawal rates (3.25–3.75%), accounts for healthcare bridge years before Medicare, and obsesses over savings rate rather than absolute contribution. Use this with our Retirement Income Calculator to see what your FI nest egg actually produces in monthly income.