Projects your savings year by year through retirement, then runs a thousand market simulations to answer the real question: how likely is this plan to last? Every assumption is on-screen and editable, spending is phased and includes healthcare, and nothing leaves your browser.
Share of 1,000 simulated market histories in which your money lasts to your end-of-plan age. A year covered entirely by guaranteed income counts as lasting.
The band shows where your portfolio is likely to sit each year — the 10th–90th percentile spread across all simulations, with the median line inside it. A band sinking to zero before your end-of-plan age is the shortfall risk a single-number calculator hides.
Split by tax treatment so withdrawals later are taxed correctly. A traditional-401(k) dollar is worth less than a Roth dollar.
Amounts in today's dollars. Social Security uses your benefit at full retirement age (67); the claim-age selector adjusts it (claim at 62 ≈ 70%, at 70 ≈ 124%). "COLA" means it rises with inflation.
| Source | Annual amount | Starts at | Inflation-adjusted |
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Budget from what you plan to spend, not a percentage of today's income. Turn on phasing to model an active early retirement that slows down later.
When phasing is on, this replaces the single annual-spending figure above.
| Description | Amount | At age |
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Nothing here is hidden. These are common planning defaults, deliberately a touch conservative — change any of them and watch the result move.
This is an educational estimate, not financial or tax advice. It projects one year at a time from your current age to your end-of-plan age. Before retirement it adds contributions and grows balances; after retirement it covers each year's spending from guaranteed income first, then withdraws from your accounts in order (cash → taxable → traditional → Roth), grossing up for taxes and applying required minimum distributions from age 73. The Monte Carlo draws each year's return from a normal distribution around your return assumption using the volatility above. Taxes are modeled with a single effective rate — good enough to show that account type matters, not a substitute for a tax pro. Results are only as good as your inputs.
One-tap "what if" tests. Each re-runs the simulation with a single change and shows the effect on your success rate — it does not alter your plan.
Save your current plan into slot A or B, change some inputs, save the other, and compare them side by side — "retire at 62 vs. 65," "claim Social Security at 67 vs. 70."