Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Years the money lasts
52
Outlook
Runs out after 52 years
Initial withdrawal rate (%)
4.00
Total withdrawn
$4,177,780
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How to use this
- 1Enter starting balance ($).
- 2Enter annual withdrawal ($).
- 3Enter annual return (%).
- 4Enter inflation (%).
- 5Read your years the money lasts on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
The 4% rule is a starting point, not a law. This runs your balance year by year against withdrawals, returns, and inflation.
Worked example
Using the values the calculator loads with:
Inputs
- Starting balance: 1000000 $
- Annual withdrawal: 40000 $
- Annual return: 6 %
- Inflation: 2.5 %
Results
- Years the money lasts: 52
- Outlook: Runs out after 52 years
- Initial withdrawal rate (%): 4
- Total withdrawn: $4,177,780
What each field means
Inputs
- Starting balance ($)
- The starting balance used in the calculation, measured in $. Starts at 1000000 $ so you have a working example on load.
- Annual withdrawal ($)
- The annual withdrawal used in the calculation, measured in $. Starts at 40000 $ so you have a working example on load.
- Annual return (%)
- The annual return used in the calculation, measured in %. Starts at 6 % so you have a working example on load. Accepted range: 0–20 %.
- Inflation (%)
- The inflation used in the calculation, measured in %. Starts at 2.5 % so you have a working example on load. Accepted range: 0–15 %.
Results
- Years the money lasts
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Outlook
- Returned as a plain value. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Initial withdrawal rate (%)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total withdrawn
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the safe withdrawal rate calculator work?
The 4% rule is a starting point, not a law. This runs your balance year by year against withdrawals, returns, and inflation. The underlying maths is: Each year: balance = (balance − withdrawal) × (1 + return); withdrawal grows with inflation.
What do I need to enter?
4 values: starting balance, annual withdrawal, annual return, and inflation. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the years the money lasts result mean?
It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Retirement Withdrawal Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/retirement-withdrawal
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/retirement-withdrawal" target="_blank" rel="noopener">Retirement Withdrawal Calculator — RevenueLab</a> (2026).</p>
Source: [Retirement Withdrawal Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/retirement-withdrawal) (2026).