Know your number.
Then reach it.

Test your retirement plan against every market crash since 1871. Thousands of simulations, 6 stress scenarios, one clear answer. No sign-up required.

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Portfolio Projection
FIRE target
87%
Success Rate
2041
FIRE Year
$1.2M
Target
Portfolio Survival
Cash Flow
Salary
Expenses
Investments
153 years
of market data tested
6 stress tests
crash, job loss, inflation & more
8 currencies
auto-detected from your location
No sign-up
no account needed

Professional-grade tools, zero barriers

Monte Carlo & Backtesting
Will your money last? 10,000 simulations and every market period since 1871 give you a real success probability, not a guess.
6 Stress Tests
Market crash, job loss, expense spike, high inflation, early or late retirement. One click each. See if your plan survives the worst.
3 Withdrawal Strategies
How should you spend down your accounts? Tax-efficient, proportional, or custom order. 59.5 early withdrawal rules built in.
Life Events
Home purchase, inheritance, career change. Each with a date and amount.
Income & Expenses
Timed streams with individual inflation rates, growth rates, and timelines.
9 Asset Types
401(k), IRA, Roth, HSA, brokerage, real estate, crypto, cash, and custom.
8 Countries
US, UK, EU, Japan, Canada, Australia, Switzerland, India. Currency and locale auto-detected.
Works on every device
Full experience on phone, tablet, and desktop. No features removed.
Export & Share
CSV export, import, and shareable URLs. Full data portability.
Your data, your browser. Export anytime.
Based on 153 years of Shiller S&P 500 data
Open methodology. See how the math works.

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Frequently Asked Questions

Your FIRE number is the total amount of money you need invested to cover your living expenses indefinitely without working. It's calculated by multiplying your annual expenses by 25 (based on the 4% safe withdrawal rate). For example, if you spend $40,000 per year, your FIRE number is $1,000,000.

Yes, as a starting point. The 4% rule is based on historical U.S. market data and has a 95% success rate over 30-year periods. However, it's not a guarantee—it's a guideline. For early retirees (40+ year retirements), consider using 3.5% for extra safety. The key is flexibility: if the market tanks early in your retirement, being willing to cut spending temporarily dramatically improves your odds.

The original Trinity study looked at 30-year periods. For longer retirements, you have options: use a more conservative 3-3.5% withdrawal rate (28-33x expenses), plan to earn some income in early retirement, or build in flexibility to reduce spending during market downturns. Historically, portfolios using the 4% rule often grew over 30 years rather than depleting, suggesting it works for longer periods too—but there are no guarantees.

Yes. All calculators support 8 currencies: USD ($), EUR (€), GBP (£), JPY (¥), CAD, AUD, CHF, and INR (₹). Use the currency selector in the navigation bar to switch. All calculations work the same regardless of currency—the math behind FIRE is universal. Your preference is saved automatically.