Disclaimer

This tool is for educational and planning purposes only. It does not constitute financial advice. Results are estimates based on historical data and assumptions that may not reflect future outcomes. Your financial data stays in your browser and is never sent to any server. Email addresses submitted for notifications are stored separately. Not affiliated with any government agency.

Not financial advice

RetireTool provides general, non-personalised calculators. It does not know your circumstances, goals, tax position, or risk tolerance, and it cannot tell you what to do with your money. Nothing here is a recommendation to buy or sell any investment product. Please consult a licensed financial adviser before making decisions.

What the projections assume

• Fixed-return projections assume the same return every single year. Real markets do not behave this way, and a sequence of poor early returns can ruin a plan that looks safe on average.
• Backtests assume annual rebalancing with no transaction costs, fees, or taxes. Real portfolios incur all three.
• All bundled return series are in nominal US dollars. No currency conversion is applied.
• Withdrawals are modelled as taken at the start of each year, before that year's return is applied.

The limits of historical backtesting

Our backtest replays your plan across every available historical starting year. This is a well-established method, but it has a known statistical weakness: adjacent windows overlap heavily — two 30-year windows one year apart share 29 years of data — so the results are highly correlated and the effective sample size is far smaller than the number of windows suggests. A "95% success rate" reflects a limited slice of history, not a probability of your future succeeding.

A percentage-of-balance withdrawal strategy cannot mathematically deplete a portfolio, so its success rate will always approach 100%. That is an artefact of the strategy, not evidence of safety — the real risk it carries is a collapse in income.

Data sources and accuracy

Historical series bundled with this site are compiled from publicly available reference data:

• S&P 500 (total return) (1928–2026) — Damodaran / NYU Stern public dataset
• US 10-Year Treasury (total return) (1928–2026) — Damodaran / NYU Stern public dataset
• US Total Market (Wilshire 5000) (1971–2026) — Wilshire index factsheets
• Small-Cap (Russell 2000) (1979–2026) — FTSE Russell published index returns
• Nasdaq-100 (1986–2026) — Nasdaq published index returns
• Real Estate (NAREIT All Equity REITs) (1972–2026) — Nareit published index returns
• Gold (spot) (1968–2026) — London bullion market reference prices
• US CPI inflation (1928–2024) — US Bureau of Labor Statistics
• ETF total returns (SPY, QQQ, SOXX, XLK/XLV/XLF, ARKK, SCHD/VIG/VYM, VXUS/VWO, TLT/IEF/BND/LQD, DIA) (inception–2026) — Published fund total returns — verify provenance before launch

We make no warranty as to their completeness or accuracy. Index names and ETF tickers are shown only to help you identify which asset class a series represents; they are the trademarks of their respective owners and their appearance here is not an endorsement or a recommendation.

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