Retirement Calculator

Understanding Retirement Planning

The landmark Trinity Study (1998) analyzed stock and bond returns from 1926 through 1995 across rolling 15- to 30-year periods. Its key finding: a 4% initial withdrawal rate from a 50/50 stock-bond portfolio survived 100% of historical 30-year periods. At 5%, the success rate dropped to 68%. This research underpins most modern retirement planning. Fidelity's widely-cited savings milestones suggest: 1× your salary saved by 30, 3× by 40, 6× by 50, 8× by 60, and 10× by 67. These assume a 15% savings rate (including employer match), age-based asset allocation, and retirement at 67 planning through age 93. Healthcare is a critical and often underestimated cost. Fidelity estimates a 65-year-old retiring today needs approximately $172,500 for lifetime healthcare expenses — and that excludes long-term care. For a couple, the figure approaches $330,000. This cost has more than doubled since Fidelity began tracking it in 2002. Retirement duration is increasing. The average American retires at 62, but life expectancy at 65 is now 84.5 years — and for a 65-year-old couple, there's a 50% chance at least one partner lives to 93. Planning for a 25- to 30-year retirement is prudent. The power of starting early cannot be overstated. At 7% annual returns, contributing $200/month from age 25 produces ~$613,000 by 65. Starting at 35 yields only ~$278,000 — a 55% reduction from just a 10-year delay. The majority of the final balance comes from compounded returns, not contributions.

Methodology

The calculator projects savings growth using the compound interest formula: FV = PV(1+r)^n + PMT × [((1+r)^n - 1) / r], where PV is your current savings, r is the monthly return rate, n is months until retirement, and PMT is your monthly contribution. To determine how much you need, the calculator computes the present value of your desired annual income over your entire retirement period (retirement age to life expectancy), adjusted for inflation. This uses the annuity formula with your real return rate (nominal return minus inflation). The readiness assessment compares projected savings against the required nest egg. A score above 100% means you're on track; below suggests you need higher contributions, a longer timeline, or adjusted expectations. The 4% rule — based on the Trinity Study — provides a widely-used benchmark: multiply your desired annual income by 25 to estimate the savings needed.

Understanding Your Results

The chart shows your projected savings growth over time, with the colored area representing total portfolio value (contributions plus investment growth). Green means you're on track; yellow and red indicate increasing shortfalls. The three most powerful levers are time, contribution rate, and return rate. Of these, time has the greatest impact because of compounding. At 7% annual returns, $200/month started at age 25 grows to ~$613,000 by 65 — but started at 35, it reaches only ~$278,000. That 10-year delay costs more than half the final balance despite contributing only $24,000 less. The 4% rule provides a practical benchmark: a $1 million retirement fund supports approximately $40,000/year in withdrawals. To target $60,000/year, you'd need about $1.5 million. Remember that Social Security typically replaces only about 40% of pre-retirement income for average earners, so personal savings must cover the gap.

Practical Examples

Scenario 1 — The early starter: Age 25, $10,000 saved, contributing $500/month at 7% return. By 65, this grows to approximately $1.35 million — supporting $54,000/year under the 4% rule, plus Social Security. Starting just 10 years later with the same inputs yields only ~$630,000. Scenario 2 — The mid-career catch-up: Age 45, $150,000 saved, contributing $1,500/month at 7% return. By 65, this reaches approximately $1.1 million. To hit $1.5 million (supporting $60,000/year), the monthly contribution would need to increase to roughly $2,200. Scenario 3 — The near-retiree: Age 58, $600,000 saved, contributing $2,000/month at 6% return (more conservative). By 65, this grows to approximately $920,000 — potentially tight for $60,000/year needs. Options include delaying retirement by 2–3 years, reducing desired income, or considering part-time work.

Tips for Retirement Planning

1. Maximize employer match first — if your employer matches 401(k) contributions, contribute at least enough to get the full match. It's an instant 50–100% return on your money. 2. Use Fidelity's milestones as checkpoints — aim for 1× salary by 30, 3× by 40, 6× by 50, and 10× by 67. If behind, increase contributions by 1% per year until you catch up. 3. Account for healthcare costs — Fidelity estimates $172,500 per person for lifetime healthcare in retirement. Build this into your savings target, not as an afterthought. 4. Plan for a longer retirement than expected — with a 50% chance one spouse lives to 93, planning for only 20 years of retirement is risky. Model for 25–30 years to be safe. 5. Consider the real return rate — enter 4–5% (not 7%) if you want inflation-adjusted projections. A 7% nominal return minus ~2.5% inflation gives roughly 4.5% real growth. 6. Don't forget Social Security — it replaces approximately 40% of pre-retirement income for average earners. Factor this in when determining how much your savings need to provide.

Sources

• Social Security Administration – Retirement Benefits
• IRS – Retirement Topics and Contribution Limits
• SEC Investor.gov – Retirement Estimator
• Fidelity – Retirement Savings Guidelines
• SSA – Primary Insurance Amount (PIA) Formula