The tax cost of converting Traditional → Roth, plus your bracket headroom.
About the Roth Conversion calculator
A Roth conversion moves money from a Traditional IRA or 401(k) into a Roth account, and the converted amount is taxed as ordinary income in the year you convert. Done strategically — in lower-income years, or filling up a tax bracket — conversions can cut your lifetime tax bill and shrink future required minimum distributions. This calculator shows the federal and state tax cost of a conversion and how much room you have left in your current bracket.
Frequently asked questions
How is a Roth conversion taxed?
The amount you convert is added to your ordinary income for the year and taxed at your marginal rate. There's no early-withdrawal penalty, but the tax is due for the year of the conversion.
What is bracket headroom?
The additional income you can recognize before your next-higher federal tax bracket begins. It's a common target for sizing a conversion so you 'fill up' a bracket without spilling into the next one.
When is the best time to do a Roth conversion?
Often in lower-income years — early retirement before Social Security and required minimum distributions begin, or any year your income dips — when your marginal rate is temporarily low.
Do Roth conversions affect Medicare IRMAA or ACA subsidies?
Yes. The added income can raise Medicare IRMAA surcharges or reduce ACA premium subsidies, so the full cost of a conversion can exceed the income tax alone.