Retirement Planning Calculator Show Advanced 1) Basics Current Age Retire Age Plan To Age (life expectancy) Current Retirement Savings Monthly Contribution (today) Contribution Growth / yr (%) 2) Returns & Inflation Pre-Ret Return / yr (%) In-Ret Return / yr (%) Inflation / yr (%) Pre-Ret Volatility / yr (%) In-Ret Volatility / yr (%) Effective Tax on Withdrawals (%) Tip: Returns are long-run averages. Volatility enables the optional Monte Carlo simulation. 3) Retirement Spending & Income Monthly Spending Goal (today's $) Withdrawal Rate (SWR, %) Other Retirement Income / mo Social Security / mo Social Security Start Age Index Spending to Inflation? YesNo Your spending goal is in today's dollars. We'll inflate it to retirement and keep it indexed if you choose. 4) Quick Monte Carlo (optional) Number of Runs Seed (optional) Confidence Band 50% (median band) 68% (~1σ) 90% Set runs to 0 to skip simulation. Higher runs look smoother but take longer. Calculate Reset Export CSV Target Nest Egg (needed at retirement)$0 Projected Nest Egg (at retirement)$0 Gap / Surplus$0 Sustainable Income (SWR × balance)$0/mo Success Probability (Monte Carlo)— Funds Last To Age (median)— Projected Balance MC Band (optional) Target at Retirement Yearly Projection AgeYearStart BalanceContribGrowthIncome InSpending OutEnd Balance Notes & Assumptions Contributions are monthly and can grow each year (advanced). We inflate your spending goal to retirement; “index spending” keeps it rising with inflation. Monte Carlo uses monthly steps with normal returns from your mean & volatility (simple model). Educational tool—this is not investment, tax, or legal advice.
