Retirement Calculator

Formula

FV = PV(1+r)^n + PMT×(((1+r)^n − 1)/r). Sustainable need = annual spend × (1 − (1+real)^−years)/real.

Withdrawal math: sustainable first-year spend ≈ nest egg × withdrawal rate.

How it works

Enter current age, retirement age, life expectancy, income growth, savings rate, returns and inflation. The engine projects salary forward, compounds current savings and future contributions to retirement day, then converts the nest egg into sustainable annual income using a real (inflation-adjusted) withdrawal rate. The gap between needed income and Social Security plus other income is the savings target.

Assumptions

• Constant pre- and post-retirement returns; no market crash sequencing.
• Inflation steady at your input; Social Security in today’s dollars unless indexed.
• Withdrawals at year-start; taxes modeled as a flat drag, not brackets.

Default result

With Defaults: age 30→65, $75,000 income, 10% saved, $50,000 current, 7% return, 3% inflation: need $1,988,773.55 · projected $3,451,175.79 · gap $-1,462,402.24

Worked examples

Mid-career saver

Age 30→65, $75,000 income +3%/yr, 10% saved, $50,000 now, 7% return, 3% inflation

need $1,988,773.55 · projected $3,451,175.79 · gap $-1,462,402.24 — Example calculated with this calculator's formula.

Late starter

Age 50→67, $90,000 income, 15% saved, $100,000 now, 6% return, 3% inflation

need $1,519,289.02 · projected $848,821.92 · gap $670,467.10 — Example calculated with this calculator's formula.

Frequently asked questions

What is the 4% rule?

The 4% rule says you can withdraw 4% of your nest egg in your first retirement year, then adjust that amount for inflation each year, with a high historical probability the money lasts 30 years. It comes from the 1998 Trinity Study of US market returns. Many planners treat it as a starting point and adjust for personal circumstances.

How much should I save for retirement?

Most advisors recommend saving 10–15% of your income, including employer matches. Popular milestones: 1× salary by 30, 3× by 40, 6× by 50, 8× by 60. The exact amount depends on your spending, other income, and retirement age.

What is the best age to retire?

There is no universal answer. Full retirement age for Social Security is 66–67 depending on birth year. Waiting to 70 increases benefits about 8% per year. The best age balances health, savings, guaranteed income, and lifestyle goals — run the calculator at several ages to compare.

How does inflation affect retirement planning?

Inflation erodes purchasing power: at 3% inflation, $100,000 today is worth about $55,000 in 20 years. Retirement plans must use real (inflation-adjusted) rates of return and grow withdrawals over time so spending power stays constant.