Transparent method
The formula
Worked example
Example inputs
How to interpret the result
The required minimum distribution is calculated from an official life-expectancy factor tied to the account owner's specific age, and that factor changes every single year as the owner ages, which means an RMD isn't a fixed percentage of the account. It recalculates against a shrinking factor and a moving account balance every year.
Before you rely on it
What to check
Confirm you're using the current year's correct official factor for your specific age and situation, not a factor from a prior year or a different table.
The common error
Where people go wrong with RMD calculator
Reusing last year's RMD factor or percentage as an estimate for this year. The factor changes annually with age, and the account balance it's applied against changes too, so neither piece of last year's calculation carries over unchanged.
Sensitivity evidence
How prior year-end balance changes the required minimum distribution
| Prior year-end balance | Required minimum distribution | Estimated withholding |
|---|---|---|
| $600,000 | $22,642 | $3,396 |
| $675,000 | $25,472 | $3,821 |
| $750,000worked example | $28,302 | $4,245 |
| $825,000 | $31,132 | $4,670 |
| $900,000 | $33,962 | $5,094 |
Every input, tested
Which input moves the required minimum distribution most
| Input | Tested from | To | Required minimum distribution at each end | Swing |
|---|---|---|---|---|
| Prior year-end balance | $675,000 | $825,000 | $25,472 to $31,132 | $5,660 (20%) |
| IRS distribution-period factor | 24 | 29 | $31,250 to $25,862 | $5,388 (19%) |
| Federal withholding rate | 13.0% | 17.0% | $28,302 to $28,302 | none |
Two variables at once
Required minimum distribution by prior year-end balance and IRS distribution-period factor
| Prior year-end balance \ IRS distribution-period factor | 21 | 27 | 32 |
|---|---|---|---|
| $600,000 | $28,571 | $22,222 | $18,750 |
| $675,000 | $32,143 | $25,000 | $21,094 |
| $750,000 | $35,714 | $27,778 | $23,438 |
| $825,000 | $39,286 | $30,556 | $25,781 |
| $900,000 | $42,857 | $33,333 | $28,125 |
Step by step
The worked example, input by input
| Input | Value used |
|---|---|
| Prior year-end balance | $750,000 |
| IRS distribution-period factor | 26.5 |
| Federal withholding rate | 15.0% |
| Required minimum distribution | $28,302 |
| Estimated withholding | $4,245 |
Where the inputs come from
Prior year-end balance is the account's value on December 31 of the year before the distribution year, taken from your custodian's statement. The distribution-period factor comes from the IRS Uniform Lifetime Table for your age, and 26.5 is the factor for age 73. If your spouse is the sole beneficiary and more than ten years younger, a different table applies. The withholding rate is what you choose to have taken for federal tax.
When the result stops applying
The starting age depends on birth year: 73 for those born from 1951 to 1959 and 75 for those born in 1960 or later. Missing an RMD triggers an excise tax that can be as much as 25% of the shortfall. Roth IRAs have no RMDs for the owner, and RMDs from several IRAs can be totaled and taken from one, but 401(k)s must be calculated separately.
What to compare it with
For the projection over years use the multi-year RMD calculator, and the QCD tax savings page shows how charitable gifts reduce taxable RMDs. The Roth conversion pages help lower future RMDs by shrinking pre-tax balances. The first-year RMD timing calculator explains what happens if you delay the first distribution.
People also ask
Frequently asked questions
When do RMDs start?
At age 73 for people born from 1951 to 1959 and at 75 for those born in 1960 or later. The first RMD may be delayed until April 1 of the following year.
What happens if I miss an RMD?
The IRS charges an excise tax on the amount not withdrawn, which can be 25% and drops to 10% if you correct the mistake promptly. Withdraw the shortfall as soon as you notice.
Do Roth IRAs have RMDs?
Not for the original owner. Roth 401(k)s were also exempted from lifetime RMDs starting in 2024, while inherited Roth accounts have their own rules.