Chapter 7: The Roth Conversion Window
The worksheets from Chapter 7 of Fifty-Five. Type your own numbers, or try an example from the book to see how each one works.
Your room in the bracket
The most you can convert this year and stay in the tax bracket you are in now.
The formula: Income before any conversion − Your deduction = Taxable income. Top of your bracket − Taxable income = Your room to convert
The calculator needs JavaScript. The paper worksheet below does not: it is the same arithmetic, written out.
The paper worksheet
Income before converting $__________ − Your deduction $__________ = Taxable income $__________
Top of your bracket $__________ − Taxable income $__________ = Your room $__________
Walk through it, step by step
- Add up everything you expect to earn this year before any conversion: wages, pensions, withdrawals, interest, dividends, gains, and the taxable part of any Social Security. Add one item at a time. Write the total on the first blank.
- Write your deduction on the second blank. For most people under 65 it is the 2026 standard deduction: $16,100 single, $32,200 married filing jointly. If you or your spouse is 65 or older, your deduction is larger; use the amount your tax preparer gives you.
- Subtract the second blank from the first. Write it on the third blank. That is your taxable income. If it is below zero, write $0.
- Find your column in the table: single or joint. The 2026 tops for single are $12,400 (10%), $50,400 (12%), $105,700 (22%) and $201,775 (24%). For married filing jointly they are $24,800 (10%), $100,800 (12%), $211,400 (22%) and $403,550 (24%). Go down the column until you reach the first number that is not smaller than your taxable income. That row is your bracket. Write its number on the fourth blank.
- Subtract your taxable income from the top of your bracket. Write it on the last blank. That is your room.
- Before you convert, run the checks in Step 4 of the method in this chapter: IRMAA from 63 on, any Marketplace premium tax credit, and your Social Security.
- Leave a cushion below the top. Chapter 12 explains why.
Check your answer
- Add your taxable income and your room. You should get exactly the top of your bracket. For the married couple who are both 58: $43,800 + $57,000 = $100,800. It matches.
- If you have qualified dividends or long-term capital gains, those are taxed at their own rates and stack on top of a conversion. Have your tax preparer run your numbers.
Figures this worksheet uses, and where they come from: 2026 tax brackets for single filers: 10% up to $12,400, 12% up to $50,400, 22% up to $105,700, 24% up to $201,775 of taxable income (IRS, tax inflation adjustments for tax year 2026, IR-2025-103); 2026 tax brackets for married filing jointly: 10% up to $24,800, 12% up to $100,800, 22% up to $211,400, 24% up to $403,550 of taxable income (IRS, tax inflation adjustments for tax year 2026, IR-2025-103); 2026 standard deduction, under 65: $16,100 single, $32,200 married filing jointly (IRS, tax inflation adjustments for tax year 2026, IR-2025-103).
Your conversions, year by year
How your pre-tax balance shrinks through every conversion year, and what that does to your first required minimum distribution.
The formula: Each year: Start balance × growth = Grown balance. Then Grown balance − Conversion = Year-end balance. After your last conversion: Year-end balance × Growth multiplier = Balance at your RMD age. Then that balance ÷ IRS factor = First RMD
The calculator needs JavaScript. The paper worksheet below does not: it is the same arithmetic, written out.
The paper worksheet
Row 1: Age ______ Start balance $__________ × growth = Grown balance $__________ − Conversion $__________ = Year-end balance $__________
Row 2: Age ______ Start balance $__________ × growth = Grown balance $__________ − Conversion $__________ = Year-end balance $__________
Row 3: Age ______ Start balance $__________ × growth = Grown balance $__________ − Conversion $__________ = Year-end balance $__________
Row 4: Age ______ Start balance $__________ × growth = Grown balance $__________ − Conversion $__________ = Year-end balance $__________
Row 5: Age ______ Start balance $__________ × growth = Grown balance $__________ − Conversion $__________ = Year-end balance $__________
Row 6: Age ______ Start balance $__________ × growth = Grown balance $__________ − Conversion $__________ = Year-end balance $__________
Row 7: Age ______ Start balance $__________ × growth = Grown balance $__________ − Conversion $__________ = Year-end balance $__________
Last year-end balance $__________ × Multiplier ________ = Balance at RMD age $__________
Balance at RMD age $__________ ÷ IRS factor ______ = First RMD $__________
Walk through it, step by step
- In the first row, write the age of your first conversion year and your pre-tax balance today.
- Multiply the start balance by 1.05 (or 1.07). Round to whole dollars. Write it under Grown balance.
- Write the amount you plan to convert that year under Conversion.
- Subtract the conversion from the grown balance. Write it under Year-end balance.
- Copy that year-end balance into the Start balance box of the next row. Add 1 to the age.
- Repeat Steps 2 through 5 for every conversion year. Do not skip a row.
- Take the last year-end balance. Count the years from that age to your RMD age (73 or 75). Find the multiplier for that many years in the table in Chapter 3.
- Multiply the last year-end balance by the multiplier. Write it on the first line below the table.
- Divide that by your IRS factor from Chapter 1 (26.5 at 73, 24.6 at 75). Round to whole dollars. That is your estimated first RMD.
- Compare it with the same math done with no conversions. The difference is how much smaller your forced withdrawals become.
- The Roth side works the same way, except you add each conversion instead of subtracting it.
Check your answer
- Every year-end balance should be smaller than that row's grown balance, by exactly the conversion amount.
- Add up the Conversion column. For Carol: $50,000 × 7 = $350,000. That should match the total you meant to convert.
- If the balance goes up year after year even though you are converting, your conversions are smaller than your growth. That is fine, but the RMD will not shrink much.
Figures this worksheet uses, and where they come from: Uniform Lifetime Table factors: 26.5 at age 73 and 24.6 at age 75 (IRS, Internal Revenue Bulletin 2024-33, T.D. 10001); RMD ages 73 and 75 (IRS, Internal Revenue Bulletin 2024-33, T.D. 10001).