What Is a Retirement Savings Longevity Calculator?
A retirement savings longevity calculator answers one of the most important questions in financial planning: how long will my money last? By combining your current savings balance, planned monthly withdrawals, expected investment returns, and the rate of inflation, the calculator projects the number of months and years your nest egg can sustain your lifestyle.
Unlike simple division (savings divided by monthly spending), this tool accounts for the fact that your remaining balance continues to earn returns while you draw it down. It also factors in inflation, which gradually reduces the real value of every dollar. The result is a far more accurate projection than back-of-the-envelope math can provide.
How to Use This Calculator
- 1
Enter Your Savings
Type the total amount you have saved for retirement. Include 401(k), IRA, brokerage, and any other investment accounts you plan to draw from.
- 2
Set Monthly Withdrawal
Enter the amount you plan to withdraw each month. If you receive Social Security or a pension, subtract that income first and enter only the gap your savings must cover.
- 3
Specify Annual Rate of Return
Enter the annual return you expect from your portfolio. A balanced stock-and-bond portfolio has historically returned around 6-7% per year before inflation.
- 4
Add Inflation Rate
Enter the expected annual inflation rate. The long-term U.S. average is about 3%. Higher inflation means your savings lose purchasing power faster.
- 5
Click Calculate
Press the Calculate button to see how many months and years your savings will last, plus the total amount withdrawn over that period.
Understanding the 4% Rule and Withdrawal Rates
The 4% rule is a widely used guideline suggesting that retirees can withdraw 4% of their portfolio in the first year of retirement, then adjust that amount for inflation each subsequent year, and have a high probability of not running out of money over a 30-year retirement. For a $500,000 portfolio, that works out to $20,000 per year or about $1,667 per month.
While the 4% rule is a useful starting point, it was based on historical U.S. market data and assumes a specific asset allocation. Your personal withdrawal rate should depend on your age at retirement, life expectancy, risk tolerance, other income sources, and current market valuations. Use this calculator to test different withdrawal amounts and see how they affect the longevity of your savings.
Why Use Our Retirement Savings Longevity Calculator?
Inflation-Adjusted Projections
Uses the Fisher equation to compute real returns so your projection reflects actual purchasing power, not just nominal dollars.
Instant Scenario Testing
Adjust any input and recalculate immediately to compare different withdrawal rates, return assumptions, or inflation scenarios.
Clear Timeline
See exactly how many months and years your savings will last, plus the total amount you will withdraw over that period.
Private & Secure
All calculations happen in your browser. No financial data is sent to any server or stored anywhere.
Tips for Making Your Retirement Savings Last Longer
Start by reducing your withdrawal rate. Even a small decrease from $2,500 to $2,000 per month can add years to your savings. Consider a flexible withdrawal strategy where you reduce spending during market downturns and increase it during strong years. This approach, sometimes called the "guardrails" method, can significantly extend the life of your portfolio.
Delaying Social Security benefits from age 62 to 67 or even 70 increases your monthly benefit substantially, which means you need to withdraw less from savings. Also consider keeping a portion of your portfolio in growth-oriented investments even during retirement. While bonds provide stability, some equity exposure helps your portfolio keep pace with inflation over a multi-decade retirement.