RMD Calculator

Use this RMD calculator to find the required minimum distribution for a chosen tax year using your prior year-end account balance and the IRS life expectancy factor. It also handles the special case where your spouse is the sole beneficiary and more than 10 years younger.

How to use our RMD Calculator

1. Select the RMD tax year (the year you are taking the distribution).
2. Enter the account balance on December 31 of the prior year (for example, use 12/31/2025 for a 2026 RMD).
3. Enter your date of birth so the calculator can find your age for the IRS table in that year.
4. Choose the IRS table: pick Uniform Lifetime for most people, or Joint and Last Survivor only if your spouse is your sole beneficiary and more than 10 years younger.
5. Confirm the age method (the default uses your age in the RMD year, which is how the IRS table ages are typically used).
6. Optional: If you picked the Joint table, open Advanced options and enter your spouse date of birth.
7. Optional: In Advanced options, pick whether this is your first RMD year to get a deadline reminder (this does not change the RMD math).
8. Optional: Choose how many future years to show in the schedule (1 to 50) to see how the factor and RMD usually change as you get older (using a constant-balance assumption).
9. Click Calculate and review the factor used, the RMD amount, and any notes or warnings.

Definitions

RMD (required minimum distribution): The minimum amount you must withdraw from certain retirement accounts for a year once RMD rules apply.

Prior year-end balance: Your account value as of December 31 of the year before the RMD tax year (the number used in the RMD calculation).

Distribution period (life expectancy factor): The IRS table number you divide your prior year-end balance by to get your RMD. It is also called a life expectancy factor. [1]

Uniform Lifetime Table: The IRS table most account owners use to find the factor based on their age. [1]

Joint and Last Survivor Table: The IRS table used only when your spouse is the sole beneficiary and is more than 10 years younger; it uses both ages. [2]

RMD tax year: The calendar year the RMD is for (even if you end up taking it early in the next year under a first-year rule).

Methodology

What this calculator does

For a chosen RMD tax year, the calculator (1) finds your age for that year, (2) selects the correct IRS life expectancy table based on your choice and spouse condition, (3) looks up the distribution period factor, and (4) calculates RMD as balance divided by factor. The IRS tables and the spouse exception are described in IRS guidance and tables. [1] [2]

Step 1: Age used for the IRS factor

The calculator uses your age in the selected RMD tax year (the age you turn on your birthday in that year). Your birthday does not need to have happened yet in that year.

owner_age_years = rmd_year - birth_year

If Joint table mode is selected, it computes spouse age the same way.

spouse_age_years = rmd_year - spouse_birth_year

Step 2: Table selection and spouse age-gap check

Uniform Lifetime is used for most people. Joint and Last Survivor is only appropriate when your spouse is the sole beneficiary and more than 10 years younger. If you select the Joint table but the age-gap test is not met, the calculator shows a warning and switches to Uniform Lifetime for safety. [2]

is_more_than_10_younger = (spouse_age_years <= owner_age_years - 11)

Step 3: Factor lookup

The calculator looks up the distribution period factor from the IRS table based on the age (Uniform) or the age pair (Joint). If the factor is not available for the computed age(s), the factor and RMD output show N/A. [1]

distribution_period_factor = factor_uniform(owner_age_years) // Uniform Lifetime

distribution_period_factor = factor_joint(owner_age_years, spouse_age_years) // Joint and Last Survivor

Step 4: RMD amount

The RMD is the prior year-end balance divided by the factor. Money is formatted in USD with 2 decimals.

rmd_amount = prior_year_end_balance / distribution_period_factor

Deadline reminder logic (text only)

The deadline note is a plain-language reminder based on whether you say it is your first RMD year. It does not change the RMD amount. General timing guidance comes from IRS RMD rules and FAQs. [3]

Optional schedule (constant balance)

If you request a schedule, the calculator repeats the same steps for each future year, keeping the balance constant so you can see how the IRS factor change affects the RMD without guessing investment returns.

rmd_y = prior_year_end_balance / factor(table, age_in_year_y)

Validation and edge cases

The calculator blocks results (with an error message) if required fields are missing, the balance is not a number or is less than or equal to 0, dates are invalid, ages are not plausible, Joint mode is selected without a spouse birth date, or schedule years are outside 1 to 50. Tooltips and the Advanced options toggle do not clear results, but changing any input does.

Sources