Estimate taxes on converting a Traditional IRA to a Roth IRA and compare long-term wealth outcomes
Enter your income details, IRA balance, and tax information, then click Calculate to estimate the cost and benefit of converting to a Roth IRA.
Estimate the tax impact of converting a Traditional IRA to a Roth IRA. The calculator applies 2026 federal tax brackets, state income tax rates, and projects long-term wealth under both scenarios.
Key assumptions:
40-year-old single filer, $120K income, $500K IRA:
Our Roth Conversion Tax Calculator estimates the federal income tax you would owe when converting funds from a traditional pre-tax retirement account to a Roth IRA. The calculation follows the same progressive tax structure the IRS uses, applying current tax brackets, your filing status, and the standard deduction to determine the tax impact of your conversion.
Enter Your Current Income
Provide your total taxable income for the year (excluding the conversion). This establishes your baseline tax bracket before the conversion.
Select Your Filing Status
Choose from Single, Married Filing Jointly, Married Filing Separately, or Head of Household. Your filing status determines the applicable tax brackets and standard deduction.
Specify the Conversion Amount
Enter how much you plan to convert from your traditional IRA or 401(k) to a Roth IRA. The entire converted amount is treated as ordinary income.
Calculate Tax Owed and Effective Rate
The calculator adds the conversion to your income, applies the standard deduction, and calculates the total federal tax with and without the conversion. The difference is your conversion tax.
Review the Detailed Breakdown
See your tax brackets before and after conversion, the marginal rate applied to your conversion, the effective tax rate, and a chart showing how the tax burden is distributed across brackets.
What makes this calculator different? Most basic calculators simply multiply your conversion amount by a single tax rate. Our calculator applies the actual progressive tax system — each portion of your conversion is taxed at the appropriate marginal rate as it fills each bracket from the bottom up. This gives you a far more accurate picture of your true tax cost.
Roth conversions are not right for everyone. The decision depends on your current tax rate, expected future tax rate, time horizon, and overall financial situation. Here is how different profiles typically compare:
Low current income means you can convert at lower tax rates. Decades of tax-free growth ahead make this the most powerful time to convert. Small conversions now can save hundreds of thousands in future taxes.
Higher income may push you into higher brackets, but strategic partial conversions during market downturns or lower-income years can still be highly beneficial. Focus on converting up to the top of your current bracket.
The window before RMDs begin is critical. Converting before claiming Social Security can keep Medicare IRMAA surcharges in check. This is often the last chance for large-scale conversions at controlled tax rates.
If you are in the highest tax brackets now, conversions may be less beneficial. Focus on tax-efficient investing and consider Roth conversions only in lower-income years or after retirement when your tax rate drops.
When you convert pre-tax retirement funds to a Roth IRA, the entire converted amount is added to your ordinary income for the year. This means the conversion is taxed at your marginal income tax rate — the rate applied to your last dollar of income. Understanding how this interacts with the progressive tax system is essential for planning an efficient conversion.
The United States uses a progressive tax system with seven federal brackets (10%, 12%, 22%, 24%, 32%, 35%, and 37%). Your income is not all taxed at the same rate. Instead, each portion of your income falls into the corresponding bracket. When you add a conversion, it fills the brackets from the bottom up, starting where your ordinary income leaves off. This means the tax on your conversion is typically lower than your highest marginal rate would suggest, because only the portion that reaches into the highest bracket is taxed at that rate.
For example, if you are a single filer earning $60,000 and you convert $40,000, your total income becomes $100,000. After the standard deduction, your taxable income is about $85,000. The first $11,600 is taxed at 10%, the next $35,550 at 12%, and the remaining $37,850 at 22%. The conversion itself spans the 12% and 22% brackets, giving you an effective tax rate on the conversion well below 22%.
Strategic conversion planning involves managing which tax brackets your conversion fills. The most common strategy is to convert up to the top of your current marginal bracket. For instance, if you have room in the 12% bracket before reaching 22%, converting exactly that amount maximizes tax efficiency. Over multiple years, you can gradually shift funds from traditional to Roth accounts while staying in lower brackets.
Follow these steps to use the Roth Conversion Tax Calculator effectively:
Before You Start
Gather your most recent tax return, know your filing status, and have a clear picture of your total income for the current year.
Enter your annual income
Input your total expected ordinary income for the current year, excluding the Roth conversion. Include salary, freelance income, business income, rental income, and any other taxable sources.
Select your filing status
Choose Single, Married Filing Jointly, Married Filing Separately, or Head of Household. Your choice affects tax bracket thresholds and standard deduction amounts.
Enter the amount you want to convert
This is the dollar amount of pre-tax retirement funds you are considering moving to a Roth IRA. Start with a conservative amount and adjust as you see the tax impact.
Review the results
The calculator shows your estimated tax on conversion, the effective tax rate, a breakdown of which brackets the conversion spans, and a comparison of your tax situation with and without the conversion.
Adjust and optimize
Try different conversion amounts to find the sweet spot where you are maximizing the use of lower tax brackets without pushing too much income into higher brackets. Use the breakdown chart to visualize the impact.
The additional income from a Roth conversion can trigger higher Medicare Part B and Part D premiums through IRMAA. These surcharges apply to individuals with modified adjusted gross income above $103,000 (single) or $206,000 (married filing jointly) in 2026. A large one-time conversion could increase your premiums for two years. Plan conversions to stay below IRMAA thresholds or account for the added cost.
Required Minimum Distributions from traditional retirement accounts begin at age 73 or 75, and they can push you into significantly higher tax brackets in retirement. By converting to Roth now, you reduce your future RMDs and potentially avoid higher taxes later. Consider projecting your RMDs at age 75 and 80 to see how conversions today reduce your future tax burden.
Most states tax Roth conversions as ordinary income, but nine states have no income tax (AK, FL, NV, NH, SD, TN, TX, WA, WY). Some states offer special treatment for retirement income or conversions. Consider how your state treats Roth conversions — moving to a tax-free state before converting could save you an additional 5–10% in state taxes on the converted amount.
The Tax Cuts and Jobs Act of 2017 lowered individual tax rates through 2025. After 2025, rates are scheduled to revert to higher 2017 levels unless Congress acts. This creates a powerful incentive to convert before rates potentially increase. Even if rates stay the same, converting during a temporary dip in your income or during a market downturn (when account values are lower) reduces the tax cost per dollar converted.
The longer your time horizon, the more powerful a Roth conversion becomes. Tax-free growth over 20–30 years can dramatically outweigh the upfront tax cost. A $50,000 conversion costing $6,000 in taxes today could grow to $200,000 tax-free over 25 years. If your time horizon is short (under 5 years), the math is less compelling since there is less time for tax-free compounding to offset the conversion cost.
Roth IRAs are powerful estate planning tools. Heirs who inherit a Roth IRA can take tax-free distributions over their lifetime (under the SECURE Act's 10-year rule), whereas inherited Traditional IRA distributions are fully taxable. Converting to Roth not only benefits you but also leaves a tax-free legacy for your beneficiaries. This can be especially valuable if you plan to leave retirement accounts to children who are in their peak earning years.
Convert During Low-Income Years
Take advantage of years when your income is temporarily lower — between jobs, during a sabbatical, after a business loss, or in early retirement before Social Security and RMDs begin. These windows allow you to convert large amounts at lower marginal rates.
Convert During Market Downturns
When account values drop, you can convert more shares for the same tax cost. A market correction effectively discounts your conversion tax. When the market recovers, that growth happens entirely inside your Roth IRA, tax-free.
Fill the Bracket Gap
Identify the gap between your current taxable income and the top of your current marginal bracket. Convert exactly that amount each year to maximize the use of your lowest available rates. This multi-year approach minimizes overall tax cost.
Pay Taxes from Taxable Accounts
Always pay the conversion tax using funds from a taxable savings or brokerage account. Withholding taxes from the conversion itself reduces your Roth balance and may trigger early withdrawal penalties. Using external funds preserves the full benefit of the conversion.
Combine with Tax-Loss Harvesting
If you have capital losses in your taxable accounts, use tax-loss harvesting to offset up to $3,000 of ordinary income per year (plus capital gains). This reduces your taxable income, creating more room in lower brackets for a Roth conversion.
Use the Spousal IRA Strategy
If you are married and have both Traditional and Roth IRAs, consider converting each spouse's accounts separately. You can optimize each spouse's bracket filling independently. A non-working spouse can also convert based on the couple's joint filing status.
Important: Roth conversion rules and tax implications are complex. The optimal strategy depends on your unique financial situation, including your current and projected future tax rates, retirement timeline, state of residence, and estate planning goals. Consult a qualified tax professional or financial advisor before implementing any conversion strategy.
The Roth Conversion Tax Calculator is provided for informational and educational purposes only. It produces estimates based on current federal income tax brackets and standard tax rules and should not be considered as professional tax advice, financial planning guidance, or a substitute for consultation with qualified professionals.
Tax laws are complex, vary by state and locality, and are subject to change. This calculator may not account for all factors that could affect your actual tax liability, including the Net Investment Income Tax (NIIT), Alternative Minimum Tax (AMT), state and local income taxes, Medicare IRMAA surcharges, the pro-rata rule for after-tax IRA basis, the impact of Roth conversions on financial aid eligibility, or specific provisions of your employer's retirement plan.
We strongly recommend consulting with a licensed tax professional, certified financial planner, or retirement planning specialist who is familiar with your specific financial situation before making any Roth conversion decisions. The accuracy of the calculator depends on the accuracy of the information you provide, and actual tax results may vary based on your complete tax picture.
By using this calculator, you acknowledge that Measurely and its operators assume no liability for any losses, taxes, penalties, or decisions made based on the calculations provided.