How the retirement estimate works

The calculator gives you a first estimate. It shows each rule it uses so you know what the answer can—and cannot—tell you.

Projection to retirement

We grow your savings by 5% per year after inflation until the retirement age you enter. “After inflation” means the result stays in today's dollars. We also add the amount you save each month.

Estimated retirement income

We estimate that savings can provide 4% of the balance in the first year. We divide that amount by 12. Then we add Social Security, pensions, and other monthly income you entered.

Coverage percentage

We divide estimated monthly income by your spending goal. A result of 100% means the two numbers match under these rules. It does not mean there is a 100% chance your plan will work.

Why 5% may be high or low

A 5% return after inflation may be fair for one mix of investments and too high for another. Returns change from year to year. Fees, taxes, and bad markets early in retirement also matter. This estimate is not a promise.

How the weekly What-If Labs work

Each lab tests one choice at a time. The sliders change the numbers and the picture. A lab may use steady growth, a 4% first-year withdrawal, or another simple rule. These examples teach how a choice works. They are not forecasts or personal advice. Each lab lists what it leaves out.

What the calculator leaves out

• Federal and state taxes
• Good and bad market years in a different order
• Different Social Security start ages and survivor benefits
• Health insurance, Medicare costs, and long-term care
• Required withdrawals, Roth conversions, and which account pays first
• Changes in spending, fees, and how long you may live

How to use the result

Use the result to find your next question. It may be spending, retirement age, saving, Social Security, or other income. Before you make a big choice that is hard to undo, check the full plan with qualified professionals.