Retirement Savings Calculator
Project your retirement savings, estimate monthly income using the 4% rule, and see inflation-adjusted value.
Projected Savings at 65
$1,188,181
Inflation-Adjusted
$422,260
Monthly Income (4% rule)
$1,408
Years in Retirement
25 yrs
Investment Period
35 yrs
How to Use This Retirement Savings Calculator
1. Enter Your Current Age. Enter how old you are today. This sets the starting point for your Investment Period.
2. Enter Your Retirement Age. Enter the age you're planning to retire. Together with your current age, this determines how many years your contributions have to grow.
3. Enter Your Current Savings. Enter what you already have saved toward retirement, whether that's in a 401(k), IRA, brokerage account, or a combination.
4. Enter Your Monthly Contribution. Enter how much you're adding each month. Even modest increases here compound significantly over a multi-decade timeline.
5. Enter Your Expected Return. Enter your assumed annual growth rate. A diversified stock portfolio's long-run historical average is a common starting point, though a more conservative number is safer for planning purposes.
6. Enter Your Inflation Rate. Enter your assumed annual inflation rate (3% is a typical default). This is what converts your nominal projected balance into today's real purchasing power.
7. Read Your Results. Projected Savings at 65 is your nominal future balance. Inflation-Adjusted shows what that balance is actually worth in today's dollars. Monthly Income applies the 4% rule to that inflation-adjusted figure. Years in Retirement shows how long that income would last — but read the fine print on this one: it assumes your portfolio earns nothing at all once you stop working, which makes it a deliberately conservative floor rather than a realistic estimate.
Robert is 30 years from retirement and runs his numbers: Projected Savings at 65 comes out to $1,188,181, which works out to $422,260 once adjusted for inflation. Using the 4% rule, that gives him $1,408 a month in retirement income — and the calculator shows Years in Retirement at 25 years. That number worries him at first, since he's hoping to live well past 90. But then he notices the explanation underneath: this 25-year figure assumes his portfolio earns zero return once he starts withdrawing from it, which isn't how retirement portfolios actually behave. Curious, he looks into how the 4% rule was originally tested and finds that historical market data — with real, continued growth during retirement — has never depleted a 4%-rule portfolio in under roughly 33 years, and most scenarios stretched to 50 years or more. Robert realizes the "25 years" on his screen isn't a prediction of when his money runs out — it's a stress-tested worst-case floor, assuming the money just sits still.
Key Terms
4% Rule
A retirement withdrawal guideline suggesting you can withdraw 4% of your portfolio's value in year one, then adjust that amount for inflation each year after, without depleting your savings over a typical multi-decade retirement.
Inflation-Adjusted Value
Your projected balance converted into today's purchasing power, based on your entered inflation rate. This number matters more than the nominal projected balance, since it reflects what your money will actually buy.
Monthly Income (4% Rule)
Your inflation-adjusted balance multiplied by 4%, divided by 12 — an estimate of sustainable monthly retirement income under the 4% rule.
Years in Retirement
How long your projected income would last assuming zero investment growth during retirement. This is intentionally the most conservative possible estimate, not a realistic timeline for a portfolio that stays invested.
Investment Period
The number of years between your current age and your retirement age — how long your contributions and current savings have to compound before you start withdrawing.
Why "Years in Retirement" Shows a Worst-Case Floor, Not Your Real Timeline
The Years in Retirement number on this calculator looks like a countdown to running out of money. It isn't — it's closer to a stress test, and understanding the difference changes how you should read it.
What "Zero Growth" Actually Means Here
This figure is calculated by simply dividing your monthly income by your inflation-adjusted balance, assuming the money sits there earning nothing while you draw it down. On a $422,260 balance generating $1,408 a month, that math produces 25 years. In reality, a retirement portfolio doesn't stop growing the day you retire — it keeps generating returns even as you withdraw from it, which is the entire mechanism that makes the 4% rule work in the first place.
What Actually Happens When You Add Real Growth Back In
The original research behind the 4% rule tested it against decades of real historical market data, including retirements that began right before severe downturns. Even in those worst-case starting points, a 4%-rule portfolio never ran out of money in under about 33 years — and in most historical scenarios, it lasted 50 years or longer, because continued growth during retirement offset the withdrawals.
How to Read Your Own Number
Treat your Years in Retirement figure as the floor, not the forecast — the number your plan would need to survive even if your portfolio's growth vanished entirely the day you stopped working. If that floor already covers your expected retirement length, real-world continued growth gives you a meaningful cushion on top of it. If it doesn't quite reach far enough, that's useful information too — a sign to revisit your contribution rate or retirement age before assuming the worst-case number is your only outcome.