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
Required distribution
$20,325
After-tax amount
$15,854
Estimated tax owed
$4,472
Monthly equivalent
$1,694
Life expectancy factor
24.6
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter prior year-end balance ($).
- 2Enter your age this year.
- 3Enter marginal tax rate (%).
- 4Read your required distribution on the right — it updates as you type.
- 5Hit Share to keep the scenario or send it to someone.
About this calculator
Once RMDs start, the IRS requires a withdrawal each year based on your balance and a life-expectancy factor. Missing it triggers a penalty.
Worked example
Using the values the calculator loads with:
Inputs
- Prior year-end balance: 500000 $
- Your age this year: 75
- Marginal tax rate: 22 %
Results
- Required distribution: $20,325
- After-tax amount: $15,854
- Estimated tax owed: $4,472
- Monthly equivalent: $1,694
- Life expectancy factor: 24.6
What each field means
Inputs
- Prior year-end balance ($)
- The prior year-end balance used in the calculation, measured in $. Starts at 500000 $ so you have a working example on load.
- Your age this year
- The your age this year used in the calculation. Starts at 75 so you have a working example on load. Accepted range: 70–100.
- Marginal tax rate (%)
- The marginal tax rate used in the calculation, measured in %. Starts at 22 % so you have a working example on load. Accepted range: 0–50 %.
Results
- Required distribution
- 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.
- After-tax amount
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Estimated tax owed
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly equivalent
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Life expectancy factor
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the required minimum distribution calculator work?
Once RMDs start, the IRS requires a withdrawal each year based on your balance and a life-expectancy factor. Missing it triggers a penalty. The underlying maths is: RMD = prior year-end balance ÷ IRS life expectancy factor
What do I need to enter?
3 values: prior year-end balance, your age this year, and marginal tax rate. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the required distribution 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.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). RMD Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/rmd-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/rmd-calculator" target="_blank" rel="noopener">RMD Calculator — RevenueLab</a> (2026).</p>
Source: [RMD Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/rmd-calculator) (2026).