Calculator · tax year 2026
Roth conversion: how much fits before the next bracket?
Enter your income before the conversion. The calculator finds where your taxable income sits in the brackets and how much more fits before each bracket ends.
Tax year 2026 Checked Review by
CheckedOct 19, 2026
A Roth conversion moves money from a traditional IRA or pre-tax plan to a Roth account. The pre-tax part of what you convert is ordinary income in the year of the conversion.
Because brackets are steps, the first dollars of a conversion can be taxed at your current rate and later dollars at a higher one. This calculator shows where each step begins, which is the number people mean by "bracket room".
The calculator
This calculator runs in your browser with JavaScript. Without it, the steps under How the estimate works give the same result by hand, with the same figures.
Your entries stay on this device. Nothing you type is sent anywhere.
Your estimate
Enter your numbers and choose Estimate.
Estimates for education only, from the federal figures listed below. This is general information as of the date shown, not advice for your situation. The right answer depends on your facts, so check how it applies to your own situation before you act on it.
How the estimate works
The calculator follows these steps, in this order.
- Start with your income before the conversion and subtract your deductions to get taxable income.
- Deductions: the standard deduction for your filing status (for example $16,100 single, $32,200 joint), plus $2,050 (single or head of household) or $1,650 (married) for each person who is 65 or older or blind. If you itemize, your itemized total replaces all of that.
- If anyone on the return is 65 or older, add the senior deduction of $6,000 per person, each reduced by 6% of income over $75,000 ($150,000 on a joint return). Married people filing separately cannot take it. Because a conversion raises income, it can shrink this deduction; the calculator allows for that.
- Find the bracket the next dollar of taxable income falls in, from the rate schedule for your filing status (the full schedules are under Figures used).
- The room in that bracket is the extra income that takes taxable income exactly to the bracket's top. The calculator repeats this for each bracket above, up to the top rate of 37%, which has no top.
- For a conversion amount, the tax is the tax on taxable income with the conversion minus the tax without it.
Worked example
Hypothetical example, not law and not a client
Pat and Lee file jointly, are both 66 and have 120,000 dollars of income before any conversion. They take the standard deduction.
- Deductions: $32,200 plus $1,650 twice (35,500), plus the senior deduction of $6,000 each (12,000), because their income is under $150,000. Total 47,500 dollars.
- Taxable income: 120,000 minus 47,500 is 72,500 dollars, in the 12% bracket. Tax: $2,480 plus 12% of the 47,700 over $24,800, so 8,204 dollars.
- Room: the 12% bracket ends at $100,800 of taxable income, so 28,300 dollars of conversion fits before it ends.
- A 50,000 dollar conversion: income becomes 170,000, which is 20,000 over the senior-deduction threshold, so each senior deduction shrinks by 1,200 (to 4,800). Deductions fall to 45,100, and taxable income is 124,900 dollars. Tax: $11,600 plus 22% of the 24,100 over $100,800, so 16,902 dollars.
- Tax on the conversion: 16,902 minus 8,204 is 8,698 dollars, about 17.4 cents per dollar converted, including the effect of the smaller senior deduction.
What this does not cover
- State income tax on the conversion.
- Social Security benefits becoming more taxable as income rises, and Medicare premium surcharges (IRMAA) that look back at income from two years earlier.
- Qualified dividends and long-term capital gains: a conversion can push them from one capital-gains rate to the next. All income here is treated as ordinary.
- The pro-rata rule. If you hold after-tax money in any traditional IRA, only part of a conversion is taxable; enter only the taxable part. The Backdoor Roth article walks through it.
- The net investment income tax, the alternative minimum tax, credits that phase out with income, and the five-year rules for Roth withdrawals.
- Paying the conversion tax: a conversion has no withholding unless you choose it, so estimated payments may come into play.
- Whether a conversion makes sense for you. That depends on future tax rates, heirs and cash on hand, which no calculator can see.
Read more
Articles
Glossary
The tax code
Questions
What does bracket room mean?
It is how much more taxable income fits before the next dollar is taxed at a higher rate. For a Roth conversion, it is the conversion amount that keeps the whole conversion in your current bracket.
Is a Roth conversion taxed at one rate?
No. A conversion is added to your other income, so each part is taxed at the rate of the bracket it falls in. A large conversion can span two or more brackets.
Why can the tax on a conversion be more than the bracket rate?
Because more income can also shrink deductions and credits that phase out with income, such as the senior deduction, so each converted dollar can add more than one dollar of taxable income.
Is this advice about my situation?
No. It is an estimate for education that shows how the rule works with the figures for the tax year. Your return depends on facts this page does not ask about, so check how it applies to your own situation before you act on it.
Figures used
Tax year 2026. Every figure the calculator reads comes from the verified library behind this site, with its source, the date it was checked and the date it is due for a re-check. If any figure passes its review date, the calculator pauses until it is re-checked.
| Figure | Value | Source | Checked | Review by |
|---|---|---|---|---|
Tax rate schedule: singlefederal-2026:income_tax.rate_schedules.single | 10% up to $12,400; 12% up to $50,400; 22% up to $105,700; 24% up to $201,775; 32% up to $256,225; 35% up to $640,600; 37% above $640,600 | Rev. Proc. 2025-32 sec. 4.01 | CheckedSep 24, 2026 | |
Tax rate schedule: married filing jointly or qualifying surviving spousefederal-2026:income_tax.rate_schedules.married_filing_jointly_and_surviving_spouse | 10% up to $24,800; 12% up to $100,800; 22% up to $211,400; 24% up to $403,550; 32% up to $512,450; 35% up to $768,700; 37% above $768,700 | Rev. Proc. 2025-32 sec. 4.01 | CheckedSep 24, 2026 | |
Tax rate schedule: married filing separatelyfederal-2026:income_tax.rate_schedules.married_filing_separately | 10% up to $12,400; 12% up to $50,400; 22% up to $105,700; 24% up to $201,775; 32% up to $256,225; 35% up to $384,350; 37% above $384,350 | Rev. Proc. 2025-32 sec. 4.01 | CheckedSep 24, 2026 | |
Tax rate schedule: head of householdfederal-2026:income_tax.rate_schedules.head_of_household | 10% up to $17,700; 12% up to $67,450; 22% up to $105,700; 24% up to $201,750; 32% up to $256,200; 35% up to $640,600; 37% above $640,600 | Rev. Proc. 2025-32 sec. 4.01 | CheckedSep 24, 2026 | |
Standard deduction: singlefederal-2026:standard_deduction.basic.single | $16,100 | Rev. Proc. 2025-32 sec. 4.14 | CheckedSep 24, 2026 | |
Standard deduction: married filing jointly or qualifying surviving spousefederal-2026:standard_deduction.basic.married_filing_jointly_and_surviving_spouse | $32,200 | Rev. Proc. 2025-32 sec. 4.14 | CheckedSep 24, 2026 | |
Standard deduction: married filing separatelyfederal-2026:standard_deduction.basic.married_filing_separately | $16,100 | Rev. Proc. 2025-32 sec. 4.14 | CheckedSep 24, 2026 | |
Standard deduction: head of householdfederal-2026:standard_deduction.basic.head_of_household | $24,150 | Rev. Proc. 2025-32 sec. 4.14 | CheckedSep 24, 2026 | |
Extra standard deduction per box (65 or older, or blind): married or surviving spousefederal-2026:standard_deduction.additional_aged_or_blind_per_condition.married_or_surviving_spouse | $1,650 | Rev. Proc. 2025-32 sec. 4.14 | CheckedSep 24, 2026 | |
Extra standard deduction per box (65 or older, or blind): single or head of householdfederal-2026:standard_deduction.additional_aged_or_blind_per_condition.unmarried_not_surviving_spouse | $2,050 | Rev. Proc. 2025-32 sec. 4.14 | CheckedSep 24, 2026 | |
Senior deduction per person 65 or olderfederal-2026:obbba_deductions.senior_deduction.amount_per_qualified_individual | $6,000 | 26 U.S.C. sec. 151(d)(5)(C) | CheckedSep 24, 2026 | |
Senior deduction phase-outfederal-2026:obbba_deductions.senior_deduction.phaseout | 6% of modified AGI over $75,000 ($150,000 on a joint return) | 26 U.S.C. sec. 151(d)(5)(C)(iii) | CheckedSep 24, 2026 | |
Income tax: ordinary ratesfederal-2026:income_tax.ordinary_rates | as quoted above | Rev. Proc. 2025-32 sec. 4.01 | CheckedSep 24, 2026 |