The Tax Window Calculator
There's often a stretch between the last paycheck and the day Social Security and required withdrawals kick in, when your tax bracket dips. This shows how big that window is for you in 2026, and what filling it with a Roth conversion would actually cost.
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Your 2026 numbers
Married filing separately and head of household aren't supported in this version.
Age drives the extra deduction at 65 and the Medicare income timing.
Annual, household total, the gross amount before Medicare premiums come out. Enter 0 if you haven't started.
What you already plan to pull out this year, not counting any Roth conversion.
The taxable portion.
Add wages, investment income, or deductions
Bank interest, non-qualified dividends, short-term gains.
Leave blank to use the standard deduction. Most retirees do.
Nine states have no income tax, and several (like PA and IL) don't tax retirement withdrawals at all. If unsure, leave blank and ask your CPA.
Your 2026 federal picture
Your stopping points
Print this or screenshot it, and ask your CPA exactly how much room you have. These are federal numbers. Your state may add tax on top, or none at all. Ask your CPA how your state treats a conversion.
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The idea behind this tool, in plain English: read the letter on the lowest-tax window.
Educational tool only. Estimates your 2026 federal income tax under the rules in effect for tax year 2026, using the rate schedules rather than the IRS tax tables (results can differ by a few dollars). Assumes the standard deduction unless you enter itemized deductions, and treats modified adjusted gross income as equal to AGI. Does not compute state tax, the net investment income tax, alternative minimum tax, credits, dependents, or Medicare premiums; Medicare income tiers shown are the 2026 tiers as a stand-in for future years, and your 2026 income affects premiums two years later. Not financial, legal, tax, or investment advice, and not an offer or solicitation of any investment. Consult your own licensed professionals before making financial decisions.