RMD Calculator

RMD Calculator

Once you turn 73, the IRS requires you to start withdrawing money from your traditional IRA, 401(k), and other tax-deferred accounts — whether you need the income or not. These withdrawals are called Required Minimum Distributions, and missing the deadline triggers a 25% penalty on the amount you failed to take out. This calculator divides your prior year-end account balance by the IRS Uniform Lifetime Table distribution period for your age to show your exact annual RMD and monthly equivalent.

How RMDs Are Calculated

The RMD formula is straightforward: divide the account balance as of December 31 of the prior calendar year by the distribution period assigned to your current age by the IRS Uniform Lifetime Table. The distribution period decreases each year you age, meaning a progressively higher percentage of your account must be withdrawn annually.

Annual RMD = Prior Year-End Account Balance / IRS Distribution Period for Your Age

Monthly Equivalent = Annual RMD / 12

Withdrawal Percentage = 1 / Distribution Period x 100

At age 73, the distribution period is 26.5, requiring a withdrawal of about 3.77% of the balance. At age 80 the period is 20.2 (4.95%), and at age 90 it drops to 12.2 (8.2%). Each year the divisor shrinks, so RMDs increase both because the divisor falls and because the remaining balance may have grown from investment returns.

Worked Examples

Scenario 1 — First RMD at age 73: Account balance as of December 31 of the prior year: $650,000. Distribution period at age 73: 26.5. Annual RMD: $650,000 / 26.5 = $24,528. Monthly equivalent: $2,044. If this account grew to $680,000 by the following December 31, next year’s RMD (age 74, period 25.5) would be $680,000 / 25.5 = $26,667.

Scenario 2 — Age 80 with multiple accounts: Traditional IRA balance: $420,000. 401(k) balance from a previous employer: $130,000. Distribution period at age 80: 20.2. IRA RMD: $420,000 / 20.2 = $20,792. 401(k) RMD: $130,000 / 20.2 = $6,436. Total annual RMD: $27,228. Important: the IRA RMD can be taken from any of the owner’s IRAs, but the 401(k) RMD must come specifically from that 401(k) — the two cannot be aggregated.

Scenario 3 — Spouse more than 10 years younger (Joint Life Table): Account owner is age 75, spouse (sole beneficiary) is age 60. Under the IRS Joint and Last Survivor Table, the distribution period is 27.0 years instead of the Uniform Table’s 24.6. Account balance: $500,000. RMD using the Joint Table: $500,000 / 27.0 = $18,519 — about $2,300 less than under the standard table. This exception requires the spouse to be the sole designated beneficiary of the account.

IRS Uniform Lifetime Table — Selected Ages

When to Use This Calculator

• You turned 73 this year and need to calculate your first RMD before the April 1 deadline (all subsequent RMDs are due December 31)
• You want to project future RMDs across multiple accounts as part of a tax planning strategy
• You are trying to decide whether to take Roth conversions in pre-RMD years to reduce the size of future RMDs
• You have a spouse significantly younger than you and want to confirm whether the Joint and Last Survivor Table gives you a lower distribution requirement
• You are a beneficiary of an inherited IRA and need to understand whether annual RMDs apply or the 10-year rule does

Common Mistakes

1. Using the current account balance instead of the prior December 31 balance. RMDs are calculated on the balance as of December 31 of the year before the distribution year. If you take your 2025 RMD in March 2025, the calculation uses your December 31, 2024 balance — not the March 2025 balance.
2. Aggregating 401(k) RMDs with IRA RMDs. IRA owners can aggregate all their IRA RMDs and take the total from any single IRA. But a 401(k) RMD must come from that specific 401(k) plan — you cannot satisfy it by taking extra from an IRA. Each 401(k) must be treated separately.
3. Forgetting the first-year deadline. Your first RMD can be delayed until April 1 of the year after you turn 73. But if you do, you must also take your second RMD (for the next calendar year) by December 31 of that same year — resulting in two taxable RMDs in one year, which can push you into a higher bracket and increase Medicare premiums.
4. Assuming Roth IRAs have RMDs. Roth IRAs are exempt from RMDs during the owner’s lifetime. Roth 401(k)s are also exempt starting in 2024 under SECURE 2.0. However, most non-spouse beneficiaries of inherited Roth IRAs must empty the account within 10 years under the SECURE Act.

Real-World Applications

RMDs exist because tax-deferred accounts like traditional IRAs and 401(k)s were funded with pre-tax dollars — the IRS eventually requires those funds to be withdrawn and taxed. For retirees who do not need the cash, RMDs can create taxable income that raises Medicare Part B and D premiums (Income-Related Monthly Adjustment Amount, or IRMAA), triggers taxation of Social Security benefits, or pushes investment gains into higher brackets. Proactive planning before age 73 — such as making Roth conversions in years when income is lower — can reduce the size of future RMDs and the lifetime tax bill. Qualified Charitable Distributions (QCDs) allow account owners age 70.5 or older to donate up to $105,000 per year directly from an IRA to charity, satisfying all or part of the RMD without the distribution ever appearing in adjusted gross income.

Tips

1. Mark December 31 as your annual RMD deadline — the 25% penalty for missing it is one of the stiffest in the tax code, and even a one-day delay counts as a missed distribution.
2. Set up automatic monthly distributions of 1/12 of your annual RMD to smooth cash flow and avoid scrambling for a large year-end withdrawal.
3. Consider making Roth conversions in the years between retirement and age 73 to reduce the balance subject to future RMDs and your long-term tax exposure.
4. If you do not need the income from your RMD, a Qualified Charitable Distribution (QCD) lets you send up to $105,000 directly to a qualifying charity — satisfying the RMD and keeping the amount out of your AGI entirely.
5. If your spouse is your sole beneficiary and is more than 10 years younger, file the paperwork to use the Joint and Last Survivor Table — it gives a longer distribution period and reduces your annual RMD.
6. Rolling old 401(k)s into your current employer’s plan (if still working past 73) can defer those 401(k) RMDs until you fully retire, though IRA RMDs must still be taken regardless of employment status.