Drawdown Projection Results
How to Use This Tool
Enter your initial portfolio balance, then select your withdrawal type: fixed annual amount or a percentage of your portfolio balance. Input your expected annual return rate, inflation rate, and withdrawal frequency. Choose whether to simulate over a set number of years or calculate how long your portfolio will last. Click Calculate to view your projection results, or Reset to clear all inputs.
Formula and Logic
This calculator uses period-based compounding to model portfolio drawdown. For each withdrawal period (monthly, quarterly, or annual):
- Inflation-adjusted withdrawals are deducted from the current balance first.
- Investment returns are applied to the remaining balance at your specified annual rate, compounded per period.
- For percentage-based withdrawals, the annual withdrawal amount is recalculated as a percentage of the current portfolio balance each year.
- Inflation adjustments increase the annual withdrawal amount by your specified inflation rate each year to maintain purchasing power.
The inflation-adjusted average annual return is calculated as (Expected Return Rate - Inflation Rate) for simplified planning purposes.
Practical Notes
- This tool uses pre-tax portfolio values and does not account for income, capital gains, or estate taxes that may reduce your net withdrawal amount.
- Expected return rates are hypothetical: historical stock market returns average ~7% annual before inflation, but past performance does not guarantee future results.
- Inflation rates can vary significantly over long time horizons; using a conservative estimate (2-3%) is common for retirement planning.
- This calculator assumes a static annual return rate and does not account for market volatility, sequence of returns risk, or portfolio rebalancing.
- For fixed withdrawal amounts, a 4% initial withdrawal rate (adjusted for inflation) is a widely used benchmark for 30-year retirement horizons.
Why This Tool Is Useful
It helps you test different withdrawal scenarios to avoid outliving your savings, a key risk for retirees and long-term savers. You can adjust variables to see how a higher inflation rate, lower return assumption, or larger withdrawal amount impacts portfolio longevity. Financial planners use similar models to create sustainable withdrawal plans tailored to client risk tolerance and time horizons.
Frequently Asked Questions
What is a safe withdrawal rate for most portfolios?
The 4% rule is a common benchmark, suggesting a 4% initial withdrawal adjusted for inflation annually, with a high probability of portfolio longevity over 30 years. Adjust this rate lower for longer time horizons or higher risk tolerance.
Does this calculator account for taxes on withdrawals?
No, this tool uses pre-tax portfolio values. Consult a tax professional to adjust withdrawal amounts for federal, state, and local taxes that apply to your investment accounts (e.g., 401(k), IRA, taxable brokerage).
How does inflation impact my portfolio drawdown?
Inflation reduces the purchasing power of your withdrawals over time. This calculator automatically adjusts withdrawal amounts annually for inflation to maintain your standard of living, which will increase total withdrawals over long time horizons.
Additional Guidance
- Run multiple scenarios with conservative return and inflation assumptions to stress-test your plan.
- Consider reducing withdrawal rates during market downturns to preserve portfolio balance (dynamic withdrawal strategies).
- Review your plan annually and adjust inputs as your portfolio performance, inflation, or spending needs change.
- Combine this tool with a diversified portfolio strategy to minimize sequence of returns risk in early retirement years.