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Retirement Calculator

What Is a Retirement Calculator?

A retirement calculator helps you estimate how much money you need to save to maintain your desired lifestyle after you stop working. It factors in your current savings, monthly contributions, expected investment returns, inflation, and how long you expect to live in retirement. The goal is to ensure you don't outlive your money — a fear shared by 45% of Americans according to a 2024 Gallup survey. Unlike simple savings calculators, a retirement calculator accounts for two distinct phases of your financial life: the accumulation phase (saving and investing while working) and the distribution phase (withdrawing funds in retirement). During accumulation, compound interest works in your favor; during distribution, inflation and withdrawals work against you.

How Retirement Planning Works

Retirement planning revolves around a core equation: your savings at retirement must generate enough income to cover your expenses for the rest of your life. During your working years, your money compounds — earning returns on returns. A 7% annual return doubles your money roughly every 10 years (the Rule of 72). This means $10,000 invested at age 25 becomes approximately $160,000 by age 65 without adding another dollar. The critical variables are: your savings rate, your return rate, inflation (which erodes purchasing power at roughly 3% per year), and your time horizon. Even small changes create enormous differences over decades. Increasing your savings rate by just 1% of your salary can add tens of thousands to your retirement fund over a 30-year career.

Frequently Asked Questions

How much money do I need to retire?

The most widely used rule is the 25x Rule: save 25 times your annual expenses. If you spend $60,000/year, you need $1,500,000. This is based on the 4% withdrawal rule, which historically allows a portfolio to last 30+ years. The exact amount depends on your lifestyle, healthcare needs, location, and other income sources like Social Security or pensions.

At what age can I retire?

Traditional US retirement age is 65-67 (for full Social Security benefits), but your actual retirement age depends on savings rate. Someone saving 15% can typically retire around 65. The FIRE movement shows that saving 50-70% of income can allow retirement in 10-17 years, regardless of starting age. The key factors are spending level and savings rate, not age.

What is the 4% Rule and does it still work?

Developed by William Bengen in 1994, the 4% Rule states that withdrawing 4% of your portfolio in year one, then adjusting for inflation annually, has historically allowed a 50/50 stock/bond portfolio to last at least 30 years. Recent research suggests 3.5-4% remains safe for 30-year retirements, though longer retirements (40+ years) may warrant 3-3.5%.

How does inflation affect retirement savings?

At 3% annual inflation, $1 today is worth only $0.48 in 25 years. If you need $60,000/year today, you'll need about $125,000/year in 25 years for the same lifestyle. This calculator shows both nominal and inflation-adjusted values so you see real purchasing power.

Should I max out my 401(k) or invest elsewhere?

Priority order: (1) Contribute enough to get full employer match — free money. (2) Max Roth IRA ($7,000 in 2026). (3) Max 401(k) ($23,500 in 2026). (4) Invest in taxable brokerage. This order maximizes tax benefits and employer matching.

What rate of return should I expect?

The S&P 500 has returned ~10% annually since 1926 (nominal) or ~7% after inflation. Most advisors recommend 6-7% pre-retirement and 4-5% post-retirement. Using conservative estimates is safer than being overly optimistic.

How much should I save each month?

General guideline: 15% of gross income including employer match. Starting at 25, this provides comfortable retirement at 65. Starting later requires more: at 35 aim for 20%, at 45 aim for 25-30%. Use Fidelity benchmarks to check: 1x salary by 30, 3x by 40, 6x by 50, 10x by 67.

What is FIRE (Financial Independence, Retire Early)?

FIRE focuses on extreme savings (50-70% of income) to achieve financial independence decades before 65. At 50% savings rate, retire in ~17 years; at 70%, in ~8.5 years. Variations include LeanFIRE (~$40K/year), FatFIRE ($100K+/year), and BaristaFIRE (semi-retirement with part-time work).