4% Rule Calculator

Use the 4% Rule Calculator

Your results

Safe annual withdrawal: $0.00
Safe monthly withdrawal: $0.00
Required portfolio: $0.00
Portfolio surplus or gap: $0.00

How this calculator works

What it does: Estimate how much portfolio income a withdrawal rate can support and how large a portfolio you may need.
Inputs used: The estimate uses portfolio value, withdrawal rate (%), annual expenses, and monthly expenses.
Calculation approach: The calculator applies the relationships defined for the 4% rule calculator to those inputs and updates safe annual withdrawal, safe monthly withdrawal, required portfolio, and portfolio surplus or gap.
How to read the result: Treat the result as a scenario based on the values entered. Compare a few reasonable inputs and consider costs, taxes, timing, or risks that the calculator does not include.

How to Use This Calculator

Enter Portfolio value and Withdrawal rate (%) using values that match the scenario you want to evaluate.
Enter Annual expenses and Monthly expenses using values that match the scenario you want to evaluate.
Review the assumptions for the 4% rule calculator, especially rates, time periods, and optional amounts.
Select Calculate to update the results, then adjust one input at a time to compare scenarios.

Understanding the Results

Safe annual withdrawal: The estimated payment or withdrawal amount produced by the current balance, rate, and time assumptions.
Safe monthly withdrawal: The estimated payment or withdrawal amount produced by the current balance, rate, and time assumptions.
Required portfolio: The target amount calculated from the spending, rate, or goal assumptions entered above.
Portfolio surplus or gap: The difference between the current position and the calculated target or comparison value.

Common Mistakes

Treating an assumed return, growth rate, inflation rate, or yield as guaranteed.
Leaving out taxes, fees, inflation, or timing differences that can affect real-world results.
Mixing monthly and annual figures or entering percentages in the wrong units.
Relying on one projection instead of comparing a range of reasonable assumptions.

Worked Example

Example inputs

Portfolio value: $1,000,000
Withdrawal rate (%): 4%
Annual expenses: $40,000

Example results

Safe annual withdrawal: $40,000.00
Safe monthly withdrawal: $3,333.33
Required portfolio: $1,000,000.00
Portfolio surplus or gap: $0.00

For this illustrative scenario, the safe annual withdrawal is $40,000.00. Changing any input can materially change the result, so use the example as a walkthrough rather than a guarantee.

Frequently asked questions

What is the 4% rule in the 4% Rule Calculator?

The 4% rule is a retirement planning guideline that begins with a withdrawal equal to 4% of a portfolio in the first retirement year.

Can I choose a different withdrawal rate?

Yes. Lower rates generally require a larger portfolio and may provide more flexibility, while higher rates increase withdrawal risk.

Which retirement spending amount should I enter?

Use a realistic estimate that includes housing, healthcare, food, travel, taxes, and other expected retirement expenses.

Does the 4% rule account for inflation?

The original guideline assumes later withdrawals rise with inflation, but this calculator only estimates the first-year withdrawal and portfolio target.

How is this calculator useful for FIRE planning?

It compares portfolio income with planned spending and estimates the portfolio size associated with your chosen withdrawal rate.

Does the 4% Rule Calculator include taxes or account type?

No. It does not model Roth IRA rules, 401(k) taxes, required distributions, fees, or penalties. Treat the result as a gross planning estimate.

How should I compare the 4% rule with another withdrawal rate?

Use 4% as a baseline, then test lower and higher withdrawal rates to see how the required portfolio changes under more cautious or flexible assumptions.

What does the 4% Rule Calculator calculate?

Estimate how much portfolio income a withdrawal rate can support and how large a portfolio you may need. The result is based only on the inputs and assumptions shown on the page.