Roth Conversion Calculator
See the federal tax cost of a Roth conversion and the bracket it pushes you into this year.
Want to understand the concept, not just the number? Read The Roth Conversion Guide and more below.
How it's calculated
A Roth conversion moves money from a Traditional account to a Roth, and the converted amount is added to your ordinary income for the year. The calculator taxes your income with and without the conversion, and the difference is what the conversion costs.
Take a single filer with $75,000 of taxable income who converts $25,000. That $25,000 stacks on top and is taxed in the 22% bracket, so the conversion costs about $5,500, an effective rate of 22% on the converted amount.
Timing is the whole game. Converting in a low-income year, or only up to the top of your current bracket, keeps the effective rate down. The payoff is that qualified Roth withdrawals later are tax-free, which is valuable if you expect higher rates in retirement.
Assumptions
- The converted amount is added to your ordinary income for the year and taxed at 2026 federal brackets. — IRS Rev. Proc. 2025-32
- Assumes you pay the conversion tax from outside funds. State tax and IRMAA effects are not modeled.
Last updated: 2026-08-07 · Tax year 2026
These assumptions follow our general methodology.
Frequently asked questions
When does a Roth conversion make sense?
Often when your current tax rate is lower than the rate you expect in retirement, or in a low-income year before Social Security and required distributions begin.
What is the five-year rule?
Each conversion generally must season five years before its converted principal can be withdrawn penalty-free. Talk to a tax professional about your situation.
Should I convert all at once?
Usually not. Converting a large balance in one year can push you into higher brackets and raise Medicare premiums. Many people convert smaller amounts over several years to stay inside a target bracket.