About Retirement Calculator

Projects retirement savings growth for 401(k) and IRA accounts from the current age through retirement. Factors in monthly contributions, employer match (capped at 6% of income), expected annual return, inflation, income replacement ratio, and estimated Social Security benefits. Uses the 4% withdrawal rule to determine whether projected savings meet retirement income needs, identifies any shortfall, and calculates the additional monthly contribution required to close the gap. Includes an interactive Recharts line chart showing 401(k), IRA, and total savings trajectories over time.

• Compound growth applied yearly: balance × (1 + return) + annual contributions
• Employer match calculated as a percentage of your 401(k) contribution, capped at 6% of gross income
• Future income projected using the inflation rate, then multiplied by the income replacement percentage
• 4% safe withdrawal rule: total needed = required annual income ÷ 0.04
• Shortfall calculation uses the future value of annuity formula to determine additional monthly savings needed
• Income replacement ratio displayed with a color-coded progress bar (green ≥80%, yellow ≥60%, red below)

Frequently Asked Questions

What is the 4% rule this calculator uses?

It comes from the Trinity Study: withdrawing 4% of your portfolio in year one of retirement (adjusted for inflation each subsequent year) has historically sustained a 30-year retirement. The calculator divides your required annual income by 0.04 to determine how large your nest egg needs to be.

Does this account for taxes?

No. All projections are pre-tax. In practice, 401(k) withdrawals are taxed as ordinary income, Roth IRA withdrawals are tax-free, and Social Security may be partially taxed. Adjust your income replacement target upward (e.g., 85–90% instead of 80%) to approximate the tax impact.