Introduction
A Roth conversion moves money from a traditional retirement account, like a Traditional IRA or 401(k), into a Roth IRA. You pay taxes on the money now, but it then grows tax-free and comes out tax-free in retirement. The big question is: does paying taxes today save you more money in the long run?
This Roth Conversion Calculator helps you answer that question. Enter your account balance, conversion amount, age, tax rates, and expected investment return. The calculator compares two paths side by side: keeping your money in the traditional account versus converting to a Roth. It shows you which option could leave you with more money at retirement, how long it takes the Roth to break even, and how much you would owe in taxes if you convert today.
You can also turn on advanced options to account for Required Minimum Distributions (RMDs), adjust results for inflation, and check whether the conversion could trigger Medicare IRMAA surcharges. A bracket-fill optimizer tells you how much you can convert without jumping into a higher federal tax bracket. All results update instantly with a year-by-year chart, data table, and full step-by-step math breakdown.
How to Use Our Roth Conversion Calculator
Enter details about your retirement account, age, and tax rates below. The calculator will show whether converting to a Roth IRA helps or hurts your net worth at retirement, how much tax you will owe today, and when the conversion breaks even.
Source Account Type — Pick the type of retirement account you want to convert from. Options include Traditional IRA, Rollover IRA, 401(k), 401(a), 403(b), and Governmental 457(b).
Current Account Balance — Enter the total dollar amount currently in your retirement account.
Conversion Amount — Enter how much of the balance you want to move into a Roth IRA this year. Check the "Convert full balance" box if you want to convert everything at once.
Current Age — Enter your age today. You must be between 18 and 80.
Retirement Age — Enter the age you plan to retire. This must be older than your current age, up to 100. If you are unsure when to retire, try our Retirement Calculator to explore different scenarios.
Annual Return — Enter the average yearly growth rate you expect on your investments. The default is 7%. This rate applies to both the Roth and Traditional scenarios equally. You can use our Investment Calculator to model different return assumptions on your portfolio.
Filing Status — Choose Single or Married Filing Jointly. This affects the tax bracket optimizer and IRMAA thresholds.
Current Taxable Income — Enter your taxable income this year, not counting the conversion itself. The calculator uses this to check which tax bracket you are in and how much room you have before the next bracket. If you need help determining your taxable income, our Income Tax Calculator can assist.
Current Federal Marginal Rate — Select the federal tax bracket that applies to you right now. This is the rate you will pay on the converted amount today.
Expected Federal Rate in Retirement — Select the federal tax bracket you expect to be in when you retire. A lower future rate favors keeping the Traditional IRA. A higher future rate favors converting to Roth.
Current State Tax Rate — Enter your state income tax rate today. If your state has no income tax, enter 0.
Expected State Rate in Retirement — Enter the state tax rate you expect to pay in retirement. If you plan to move to a no-tax state, enter 0.
Account for RMDs — Turn this on under Advanced Options to include Required Minimum Distributions. Traditional IRAs force you to withdraw money starting at age 73, which raises your taxable income. Roth IRAs have no RMDs.
Adjust for Inflation — Turn this on to show all future values in today's dollars using a 2.5% inflation rate. This makes it easier to understand what your money will actually be worth. Our Inflation Calculator can help you explore how purchasing power changes over time.
Medicare IRMAA Awareness Flag — Turn this on to check whether your income plus the conversion amount could trigger higher Medicare premiums. The calculator will flag which IRMAA surcharge tier you may hit. You can use our MAGI Calculator to determine your Modified Adjusted Gross Income, which is what Medicare uses for IRMAA thresholds.
Click Calculate to see your results. Click Reset to return all fields to their default values.
What Is a Roth Conversion?
A Roth conversion is when you move money from a traditional retirement account, like a Traditional IRA or 401(k), into a Roth IRA. When you do this, you pay income taxes on the amount you move now instead of paying taxes later when you withdraw the money in retirement.
Why Would You Convert to a Roth IRA?
The main reason people convert is to save money on taxes over time. If you expect your tax rate to be higher in retirement than it is today, paying taxes now at the lower rate can leave you with more money later. Once the money is in a Roth IRA, it grows tax-free thanks to compound interest, and you pay zero taxes when you take it out in retirement. Roth IRAs also have no required minimum distributions (RMDs), so you are never forced to withdraw money at a certain age.
When Does a Roth Conversion Make Sense?
A Roth conversion tends to work best when:
- Your current effective tax rate is lower than what you expect to pay in retirement.
- You have enough cash outside your retirement accounts to pay the tax bill.
- You have many years until retirement, giving the converted money more time to grow tax-free. Use the Future Value Calculator to see how tax-free compounding adds up.
- You want to reduce future RMDs that would start at age 73.
It may not make sense if your tax rate will drop significantly in retirement, or if you need to pull money from the converted account itself to cover the taxes.
How This Calculator Works
This Roth conversion calculator compares two paths side by side. In Scenario A, you keep your money in the traditional account, let it grow, and pay taxes when you withdraw in retirement. In Scenario B, you convert to a Roth IRA, pay taxes today, and let the money grow tax-free. The calculator accounts for federal and state taxes, investment growth, and the opportunity cost of paying taxes now. It then shows you which option is estimated to leave you with more money at retirement and how long it takes the Roth conversion to break even. For a broader view of your retirement readiness, try our Retirement Calculator or the Coast FIRE Calculator to see if your savings are already on track.
Key Terms to Know
- Marginal Tax Rate – The tax percentage you pay on your last dollar of income. This is the rate applied to the converted amount. Use our Tax Bracket Calculator to find yours.
- Break-Even Point – The age at which the Roth conversion starts to beat keeping the traditional account. This concept is similar to the analysis in our Social Security Break-Even Calculator.
- RMDs (Required Minimum Distributions) – Mandatory yearly withdrawals from traditional retirement accounts that begin at age 73. Roth IRAs do not have RMDs. Our RMD Calculator shows exactly how much you would be required to withdraw each year.
- IRMAA – Income-Related Monthly Adjustment Amount. A surcharge added to Medicare premiums when your income exceeds certain thresholds. A large conversion can push you above these limits.
- Bracket-Fill Strategy – Converting just enough each year to fill your current tax bracket without jumping into a higher one. This spreads the tax cost over several years.