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
Annual withdrawal
$48,000
Monthly income
$4,000.00
Total income including other sources
$48,000
Portfolio at end of horizon
$2,283,844
Year the portfolio runs out (0 = never)
0
Portfolio needed for this income
$1,200,000
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter portfolio value ($).
- 2Enter withdrawal rate (%).
- 3Enter real return after inflation (%).
- 4Enter retirement length (years).
- 5Enter other annual income (pension, ss) ($).
- 6Read your annual withdrawal on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
The 4% rule came from 30-year US historical data. For an early retirement spanning 40+ years, most planners now model 3.3–3.7% instead.
Worked example
Using the values the calculator loads with:
Inputs
- Portfolio value: 1200000 $
- Withdrawal rate: 4 %
- Real return after inflation: 5 %
- Retirement length (years): 35
- Other annual income (pension, SS): 0 $
Results
- Annual withdrawal: $48,000.00
- Monthly income: $4,000.00
- Total income including other sources: $48,000.00
- Portfolio at end of horizon: $2,283,843.69
- Year the portfolio runs out (0 = never): 0
- Portfolio needed for this income: $1,200,000.00
What each field means
Inputs
- Portfolio value ($)
- The portfolio value used in the calculation, measured in $. Starts at 1200000 $ so you have a working example on load.
- Withdrawal rate (%)
- The withdrawal rate used in the calculation, measured in %. Starts at 4 % so you have a working example on load. Accepted range: 1–10 %.
- Real return after inflation (%)
- The real return after inflation used in the calculation, measured in %. Starts at 5 % so you have a working example on load. Accepted range: -5–12 %.
- Retirement length (years)
- The retirement length (years) used in the calculation. Starts at 35 so you have a working example on load. Accepted range: 5–60.
- Other annual income (pension, SS) ($)
- The other annual income (pension, ss) used in the calculation, measured in $. Starts at 0 $ so you have a working example on load.
Results
- Annual withdrawal
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly income
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total income including other sources
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Portfolio at end of horizon
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Year the portfolio runs out (0 = never)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Portfolio needed for this income
- 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 came from 30-year US historical data. For an early retirement spanning 40+ years, most planners now model 3.3–3.7% instead. The underlying maths is: Annual withdrawal = Portfolio × SWR; depletion modelled year by year with real returns.
What do I need to enter?
5 values: portfolio value, withdrawal rate, real return after inflation, retirement length (years), and other annual income (pension, ss). Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the annual withdrawal result mean?
It is returned as a money amount in US dollars 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.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Safe Withdrawal Rate Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/safe-withdrawal-rate
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/safe-withdrawal-rate" target="_blank" rel="noopener">Safe Withdrawal Rate Calculator — RevenueLab</a> (2026).</p>
Source: [Safe Withdrawal Rate Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/safe-withdrawal-rate) (2026).