Portfolio Drawdown Calculator
Calculate how long your investments will last during retirement withdrawals
How to Use This Tool
Enter your initial portfolio value, planned annual withdrawal amount, expected investment return rate, and expected inflation rate. Select whether you want annual or monthly withdrawals. Click "Calculate Drawdown" to see how long your portfolio will last and view detailed projections including total withdrawals and adjusted amounts for future years.
Formula and Logic
This calculator uses a year-by-year projection model. Each year, the portfolio grows by the expected return rate and then decreases by the withdrawal amount. Withdrawals are adjusted annually for inflation. The calculation continues until the portfolio is depleted or reaches 100 years. For monthly withdrawals, the calculation compounds monthly returns while subtracting monthly portions of the annual withdrawal.
Practical Notes
- Conservative Returns: Use historical averages (6-7% for stocks, 2-3% for bonds) but consider your actual asset allocation.
- Inflation Impact: Even moderate inflation significantly reduces purchasing power over time - a 3% inflation rate cuts buying power in half over 24 years.
- Safe Withdrawal Rates: The traditional 4% rule suggests withdrawing 4% of your initial portfolio annually, adjusted for inflation.
- Tax Considerations: Account for tax implications - withdrawals from traditional IRAs and 401(k)s are typically taxed as ordinary income.
- Sequence of Returns Risk: Poor returns early in retirement can dramatically shorten portfolio lifespan.
Why This Tool Is Useful
Understanding how long your retirement savings will last is crucial for financial security. This calculator helps you stress-test different scenarios, adjust withdrawal strategies, and plan for various market conditions. It's particularly valuable for those approaching retirement who need to balance lifestyle goals with sustainable withdrawal rates.
Frequently Asked Questions
What is a safe withdrawal rate for retirement?
The traditional 4% rule suggests you can withdraw 4% of your initial portfolio in the first year, then adjust for inflation. However, recent research suggests 3-3.5% may be more appropriate given current market valuations and longer lifespans.
How does inflation affect my retirement withdrawals?
Inflation erodes purchasing power over time. If you withdraw $40,000 annually with 3% inflation, you'd need $66,000 in year 20 to maintain the same lifestyle. This calculator adjusts withdrawals for inflation to show real-world impact.
Should I use nominal or real returns in this calculator?
Use nominal returns (before inflation) and input your expected inflation rate separately. This gives you the most accurate picture of both portfolio growth and purchasing power preservation.
Additional Guidance
Consider running multiple scenarios with different return assumptions - optimistic, pessimistic, and most likely. Review your withdrawal strategy annually and adjust as needed based on actual portfolio performance and changing circumstances. For more precise planning, consult with a certified financial planner who can model your specific situation including tax optimization strategies.