What is a bracket-fill Roth conversion?

You convert just enough traditional IRA / pre-tax dollars to use the rest of your current ordinary bracket, and stop before the next rate. This page uses 2026 ordinary ceilings from Rev. Proc. 2025-32.

Is this taxable income or MAGI?

Taxable income after the 2026 standard or itemized deduction, before the conversion. MAGI (IRMAA, NIIT, ACA) is a different stack — pair this with the IRMAA page if you are on Medicare.

Does it include NIIT or state tax?

No. Federal ordinary rates only. A conversion can also move you across IRMAA or NIIT lines.

What about basis or pro-rata?

This sketch treats the conversion as fully taxable. After-tax basis uses Form 8606. The backdoor Roth page models pro-rata.

Runs in your browser · Last updated 7 September 2026

Free Roth Conversion Bracket-Fill Calculator (US, 2026)

Free Roth conversion bracket-fill calculator. 2026 ordinary brackets (Rev. Proc. 2025-32) — room left and tax if you spill. Browser tool — nothing is uploaded.

Filing status2026 taxable income before conversion ($)Roth conversion ($)

Ordinary brackets from Rev. Proc. 2025-32. Taxable income is after the 2026 standard or itemized deduction, before the conversion. Federal ordinary tax only — no NIIT, no state, no pro-rata basis.

Current ordinary rate

22%

Room left in this bracket

$25,700

Tax to fill the room

$5,654.00

Tax on this conversion

$2,200.00

Dollars at current rate

$10,000

Dollars that hit 24%

Dollars that hit higher brackets

Effective rate on conversion

22.0%

How to use this tool

Pick 2026 filing status and enter taxable income before any conversion.
Type the conversion you are considering (or the room this page prints).
Read tax in the current bracket versus dollars that spill into the next rate.

Worked example

Single, $80,000 taxable: the 22% bracket runs to $105,700, so $25,700 still fits at 22%. A $10,000 conversion costs $2,200 and does not spill. At $100,000 taxable the same $10,000 conversion puts $5,700 at 22% and $4,300 at 24%. Confirm Form 1040 taxable income — this is not a full return.

Frequently asked questions

What is a bracket-fill Roth conversion?: You convert just enough traditional IRA / pre-tax dollars to use the rest of your current ordinary bracket, and stop before the next rate. This page uses 2026 ordinary ceilings from Rev. Proc. 2025-32.
Is this taxable income or MAGI?: Taxable income after the 2026 standard or itemized deduction, before the conversion. MAGI (IRMAA, NIIT, ACA) is a different stack — pair this with the IRMAA page if you are on Medicare.
Does it include NIIT or state tax?: No. Federal ordinary rates only. A conversion can also move you across IRMAA or NIIT lines.
What about basis or pro-rata?: This sketch treats the conversion as fully taxable. After-tax basis uses Form 8606. The backdoor Roth page models pro-rata.
Uploaded?: No.