How to use the Roth conversion calculator
- 1 Choose your filing status and enter your other income this year.
- 2 Enter the amount to convert.
- 3 Enter the years until you withdraw, a yearly return and the tax rate you expect on withdrawals later.
- 4 Choose whether you pay the tax from savings or from the IRA, then read the tax now and the long-term result.
Worked example
A single filer with $80,000 of other income converting $50,000, paying the tax from savings. Taxable income rises from $63,900 to $113,900, adding $11,164 of federal tax (22.3% of the conversion) and moving into the 24% bracket. After 15 years at 6%, the Roth is worth about $119,828 against $120,221 for the traditional IRA after a 22% tax plus the savings kept, so at a 22% future rate it is close to break-even (22.3%). The higher income also crosses the $109,000 IRMAA threshold.
Converting wisely
- Convert in low-income years, such as early retirement before Social Security.
- Pay the tax from savings so the whole amount keeps growing.
- Stay inside a bracket: spread big conversions over several years.
- Check IRMAA if you are 63 or older.
See the room in your bracket with the Tax Bracket Calculator, Medicare premiums with the IRMAA Calculator, and future withdrawals with the RMD Calculator.
Features
Exact extra tax
Works out your 2026 federal tax with and without the conversion.
Break-even rate
The future tax rate at which converting and not converting come out the same.
IRMAA warning
Flags when the higher income could raise Medicare premiums two years later.
When to use it
Early retirement years
Low-income years before Social Security and RMDs are often the best time to convert. Check later withdrawals with the RMD Calculator.
Filling a bracket
Convert just enough to stay in your bracket. See the room left with the Tax Bracket Calculator.
Retirees on Medicare
Check premiums before converting with the IRMAA Calculator.
New Roth savers
Compare with regular contributions in the Roth IRA Calculator.
Related Tax tasks
Frequently asked questions
What is a Roth conversion?
Moving money from a traditional IRA or 401(k) into a Roth IRA. You pay income tax on the amount converted now, and qualified withdrawals later, including all the growth, are tax-free.
How much tax will I pay on a Roth conversion?
The converted amount is added to your taxable income for the year, so it is taxed at your marginal rates. In the example, converting $50,000 on top of $80,000 of income costs $11,164 in federal tax.
When does a Roth conversion make sense?
When your tax rate now is lower than the rate you expect when you withdraw, for example in early retirement, a low-income year, or if you expect tax rates to rise. It also helps heirs, who inherit Roth money tax-free.
What is the break-even tax rate?
The future tax rate at which converting and not converting give the same result. If you expect to pay more than that rate later, converting wins.
Should I pay the tax from the IRA or from savings?
Paying from savings outside the IRA is usually better: the full amount goes into the Roth and keeps growing tax-free. Paying from the IRA also counts as a distribution and may bring a 10% penalty under age 59½.
Is there an income limit for Roth conversions?
No. Anyone can convert, whatever their income. Income limits apply only to direct Roth IRA contributions.
What is the five-year rule for conversions?
Each conversion has its own five-year clock. If you are under 59½ and withdraw converted money within five years, the 10% penalty can apply to that amount.
Can I undo a Roth conversion?
No. Recharacterizing a conversion has not been allowed since 2018, so plan the amount carefully.
How does a conversion affect Medicare?
It raises your modified AGI, and Medicare premiums use the MAGI from two years earlier. A large conversion at 63 or older can mean IRMAA surcharges two years later.
Does this include state tax?
No. Federal income tax only. Most states also tax the conversion; a few have no income tax.
Results are estimates based on the official rates linked above. Confirm important figures with the issuing authority or a qualified adviser before you act on them.
Built and reviewed by Hamza Farooq, founder and lead developer
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