Enter your numbers, see your projected RMD bracket, and get a clear answer on whether to convert from a brokerage account or the IRA itself. Free, no email required.
Federal brackets only. State taxes, ACA premium subsidies, and IRMAA surcharges can shift the math significantly and aren't modeled here.
The calculator answers whether. The harder question is how much to convert each year.
Inside Lumifin, you enter your actual accounts, income, and retirement age — and see a year-by-year plan for how much to convert, which bracket to fill, and when to pause.
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Quick answers to the questions people ask before running their first conversion.
The best time to convert is in years when your tax bracket is unusually low. The classic window is after you stop working but before Social Security and Required Minimum Distributions begin, which usually means ages 60 to 72. During those years, taxable income is often a fraction of what it was while working, so converting at 12% or 22% beats the 24% or 32% rate you might pay once RMDs start at age 73. Run your own numbers above to see whether you have a window worth using.
A common approach is to convert up to the top of your current tax bracket without crossing into the next one. For example, if you are in the 12% bracket today and your projected RMD bracket is 22% or 24%, fill the 12% bracket each year until your projected RMD bracket drops. The right amount changes year by year as your income, healthcare costs, and the brackets themselves shift. Inside Lumifin, you get a year-by-year plan that updates as your situation changes.
If you have a brokerage account with cash or investments, that is almost always the better source. Paying conversion tax from the IRA itself shrinks the amount that grows tax-free in the Roth, which costs you decades of compounding. Paying from a brokerage account lets the full conversion compound, and you avoid future tax drag on dividends and capital gains in that brokerage. The calculator above shows the break-even tax rate for each path.
Each Roth conversion has its own 5-year clock. You must wait 5 calendar years from the start of the year you converted before withdrawing that specific conversion amount without a 10% penalty, if you are under 59½. After age 59½ the penalty goes away, but a separate 5-year rule still applies to earnings on Roth contributions and conversions. Most people doing conversions in their 60s do not need to worry about this, but early retirees converting in their 50s should plan around it.
Yes, and this is where most people get tripped up. A conversion raises your Modified Adjusted Gross Income (MAGI), which can wipe out ACA premium subsidies before age 65, costing many couples $10,000 to $20,000 per year in lost subsidies. After 65, a high MAGI triggers IRMAA surcharges that add several thousand dollars per year to Medicare Part B and Part D premiums. The right conversion amount weighs the future tax savings against the immediate healthcare cost.
It can be, especially if you expect a large RMD-driven jump in your tax bracket at 73, or if you want to leave money to heirs who would otherwise inherit the IRA and pay tax on it within 10 years. After 65, the math has to clear two extra hurdles: IRMAA surcharges and a shorter time horizon for tax-free growth. The break-even tax rate becomes a bigger lift, but conversions in the late 60s and early 70s can still win for high-RMD households.
Related: ACA Subsidy Calculator
Your break-even rate is the future tax rate above which converting to Roth today saves you money. If your projected RMD bracket exceeds your BETR, conversion is a net win.
Why the two rates differ: When you pay the conversion tax from a brokerage account, the full converted amount grows tax-free in Roth, and the brokerage money would have faced annual tax drag on dividends and capital gains anyway. This makes the break-even rate lower than your current bracket — conversion can win even if your future bracket is slightly below your current one.
When you pay from the IRA itself, the math is symmetric: paying the tax now versus paying it on the same dollars at withdrawal is mathematically equivalent. The break-even rate equals your current bracket — convert only if your future bracket will be higher.
Source: Vanguard, A BETR way to assess Roth IRA conversions.
