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Plan Success (Monte Carlo)

See the probability your portfolio lasts through retirement using random market return simulations.

How It Works

A Monte Carlo simulation runs hundreds or thousands of possible market paths. Each path uses random annual returns (based on your expected return and volatility). Your portfolio is drawn down by your chosen withdrawal each year. The success rate is the percentage of those paths where you still have money left at the end. No simulation can predict the real future—this tool shows you the odds under your assumptions.

Tip: Use a conservative expected return (e.g. 5–6%) and include volatility (e.g. 10–15% standard deviation) so the success rate reflects sequence-of-returns risk.

Your Plan

Starting Portfolio$1,000,000
Today’s portfolio value
Annual Withdrawal$40,000
First-year withdrawal. Optionally grow with inflation below.
Inflation Rate for Withdrawals (%)0%
0–10%. Set to 0 for flat withdrawals. Typical U.S. ~3%.
Years to Model30 yrs
e.g. 30 for a 30-year retirement
Expected Annual Return (%)6%
Long-term average return assumption
Volatility / Std Dev (%)12%
Typical stock portfolio: ~10–15%
Number of Simulations1,000 sims
More = smoother result, slower run

🔒 See Your Complete Retirement Timeline

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