Retirement Savings Calculator

What this calculator does

This calculator runs a two-phase projection of your retirement plan. In the accumulation phase, your current savings and monthly contributions grow at your expected pre-retirement return rate until your retirement age. In the decumulation phase, the portfolio continues to earn returns while you take an annual withdrawal that grows with inflation each year.

The two big levers

The two inputs that move the needle most are time and savings rate. Doubling your contribution beats almost any reasonable change in return rate, and starting 10 years earlier can match the result of contributing twice as much later. The third lever — return rate — is important but largely outside your control once you've picked a sensible asset allocation.

The 4% rule, in plain terms

The 4% rule says: in the first year of retirement, withdraw 4% of your portfolio. Each subsequent year, withdraw the same dollar amount adjusted for inflation. Historically, that schedule has supported a 30-year retirement across nearly all U.S. market conditions. Use it as a planning anchor, not a promise — and revisit your plan every few years as markets, expenses, and life evolve.

What this model can't do

• Sequence-of-returns risk. A single deterministic return rate can't capture the danger of poor early-retirement returns. Monte Carlo simulations are better for that.
• Taxes. The numbers here are pre-tax. Your after-tax income depends on the mix of pre-tax (401(k), traditional IRA), Roth, and taxable accounts.
• Social Security and pensions. Subtract those expected benefits from your target spending and use the difference as the input here.
• Healthcare cost spikes. Healthcare inflation has historically outpaced general inflation. Build in a margin of safety if you retire before Medicare eligibility.

Tips and common mistakes

• Don't use 10%+ returns. Long-run real returns on a diversified portfolio are typically 5–7% after inflation. Modeling 12% will lead to disappointment.
• Start early, even small. $200/month at age 25 beats $400/month at age 35 over a 35-year horizon.
• Capture the employer match. Not contributing enough to get your 401(k) match is leaving free money on the table.
• Plan for a long retirement. A 65-year-old today has a meaningful chance of living to 95. Plan for 30+ years.

Frequently asked questions

What is the 4% rule?

The 4% rule is a retirement-spending guideline based on a 1990s study by William Bengen. It states that withdrawing 4% of your portfolio in the first year of retirement, then adjusting that amount each year for inflation, has historically lasted at least 30 years across nearly all U.S. market scenarios. It's a starting point, not a guarantee — variations like 3.5% are often suggested for longer retirements or lower expected returns.

How much do I really need to retire?

Multiply your desired annual retirement spending by 25 (the inverse of 4%). If you want $80,000 a year, you need roughly $2 million. Adjust for Social Security, pensions, and any part-time work. Many retirees also adjust upward for healthcare costs and a longer life expectancy.

What is sequence-of-returns risk?

Sequence-of-returns risk is the danger of poor investment returns in the early years of retirement. Two retirees with the same average return over 30 years can have very different outcomes if one experiences a bad market in their first decade — they're selling investments while the portfolio is down. A single-rate calculator like this cannot model that risk; Monte Carlo simulations can.

Should I prioritize 401(k), Roth IRA, or taxable accounts?

A common order is: contribute to the 401(k) up to the employer match (free money), then max a Roth IRA if eligible, then go back to the 401(k) up to the annual limit, then taxable. Specific situations vary — a CFP or CPA can tailor this to your tax bracket and goals.

How does inflation affect my retirement?

Inflation reduces the purchasing power of fixed dollars over time. A $60,000 annual budget today needs to grow to about $99,000 in 25 years at 2% inflation, or $124,000 at 3%. This calculator grows your withdrawal each year by the inflation rate so the projection reflects real spending power.

Can I use this calculator if I have a pension or Social Security?

This calculator models only your investment portfolio. To include Social Security or a pension, subtract their expected annual benefit from your target spending and use the difference as the input here.