Roth Conversion Calculator
The Roth Conversion Calculator shows the immediate tax bill from converting pre-tax retirement savings to a Roth IRA, and whether the tax-free growth makes it worthwhile by comparing projected balances at retirement.
Educational estimate. Calculator results are for planning and information only, not financial, tax, medical, legal, or engineering advice. Verify important decisions with official sources or a qualified professional.
Roth Conversion Calculator
Traditional IRA to Roth IRA Tax Cost
📐 Formula & Method
Conversion Tax
The conversion amount is added to your income and taxed at your marginal rate. The after-tax Roth balance grows tax-free vs. the Traditional balance which is subject to RMDs and ordinary income tax.
📋 How to Use
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1
Enter the amount you want to convert.
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2
Enter your other income this year.
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3
Set years to retirement and expected return.
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4
Compare Roth vs Traditional projected balances.
Roth Conversion — When Does It Make Sense?
A Roth conversion makes sense when your current tax rate is lower than your expected retirement tax rate, when you have money outside the IRA to pay the conversion tax, or in low-income years (job loss, early retirement). SECURE 2.0 eliminated the age 72 RMD requirement for Roth 401(k)s, making Roth accounts even more attractive.
🔬 Methodology & Accuracy
Formula: Adds the conversion amount to current taxable income, estimates federal tax using 2026 brackets, then compares projected Roth tax-free growth with after-tax Traditional IRA value at retirement.
Data sources: IRS Roth IRA contribution guidance: https://www.irs.gov/publications/p590a; IRS IRA distribution guidance: https://www.irs.gov/publications/p590b; IRS 2026 tax inflation adjustments: https://www.irs.gov/newsroom/irs-releases-tax-inflation-adjustments-for-tax-year-2026-including-amendments-from-the-one-big-beautiful-bill
Last reviewed: June 2026 · General formula used: Conversion Tax · Accuracy: Results are precise to two decimal places using IEEE-754 double-precision arithmetic. Intended for educational and planning use only.
For informational purposes only. Results are estimates based on the inputs and formulas provided. For financial, tax, medical, or legal decisions, consult a qualified professional. Rates and regulations change — always verify current figures with official sources.