Retirement & Tax Planning Answers
Where to Find an Online RMD Calculator Tool
Quick answer
Singh PWM offers a free RMD Calculator that projects your required distributions and account balance forward through age 100 using current IRS life expectancy tables, along with a companion RMD Tax Cost Estimator that goes a step further and estimates the actual tax bill an RMD creates once it's stacked on top of Social Security, pensions, and other income. Beyond that, the IRS publishes the underlying worksheets for free in Publication 590-B, and most custodians, including Fidelity, Schwab, and Vanguard, offer basic calculators for accounts held there, though those typically stop at the required dollar amount and don't model the tax impact or account for holdings elsewhere.
A genuinely useful RMD calculator needs to do more than one thing well: calculate the required withdrawal amount accurately using the current IRS life expectancy tables, and ideally project that forward across multiple years so you can see how the RMD grows as the account balance changes and you age into a lower distribution period.
Singh PWM's RMD Calculator does exactly that, projecting both the required distribution and the account balance forward through age 100, which makes it useful for seeing the trajectory of RMDs over a full retirement rather than just the current year's number.
The harder and more valuable question, though, is what that RMD actually costs in taxes once it's added to everything else you're reporting that year. Singh PWM's RMD Tax Cost Estimator is built specifically to answer that, modeling the tax impact of the RMD alongside Social Security, pensions, and other income, rather than stopping at the withdrawal figure alone.
For a free, manual alternative, the IRS itself publishes the life expectancy tables and worksheets in Publication 590-B, which anyone can use to calculate an RMD by hand at no cost, though it requires doing the lookup and division yourself and offers no tax modeling.
Most custodians also build a basic RMD calculator into their own online platform for accounts held there. These are generally reliable for the specific account they cover, but they don't see accounts held at other institutions and, like the IRS worksheet, typically don't model the resulting tax cost.
Use a calculator that projects forward, not just the current year, since seeing how the RMD trajectory changes over the next decade is more useful for planning than a single year's number.
Treat any RMD amount you calculate as step one. Step two, what it actually costs in taxes, is the number that should drive decisions about withholding, Roth conversions, and QCD planning.
- Using a custodian's calculator and assuming it accounts for other retirement accounts held elsewhere.
- Stopping at the required withdrawal amount without checking the actual tax cost that amount creates.
- Running the calculation once and not revisiting it annually as the account balance and your age change the numbers.