The IRS lets your retirement accounts grow tax-deferred for decades, then insists on its cut — that is the bargain behind every traditional 401(k) and IRA. Starting at 73, you must withdraw a minimum amount each year, calculated by dividing your Prior Year-End Balance by a life-expectancy factor from the IRS Uniform Lifetime Table. This calculator applies that rule: enter your Account Balance, Your Age, and the Prior Year-End Balance, and it derives your Distribution Period (years), your Required Minimum Distribution, and the RMD as % of Balance.

With a $520,000 prior year-end balance at age 73, the distribution period is about 26.5 years, making the RMD roughly $19,600 — about 3.8% of the balance. Each year the divisor shrinks as you age, so the percentage — and usually the dollar amount — climbs steadily through your 70s, 80s, and beyond. Miss an RMD and the penalty is severe: historically 25% of the amount you should have withdrawn.

RMDs are taxable income, so they can shove you into a higher bracket and even raise Medicare premiums. Plan withdrawals strategically in your 60s — Roth conversions in low-income years can shrink the future RMD bite.

With the pre-filled defaults — Account Balance $500,000, age 73, Prior Year-End Balance $520,000 — the RMD Calculator returns Distribution Period (years) 26.0, Required Minimum Distribution $20,000.00, RMD as % of Balance 3.85%. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.