Roth conversion calculator (should you convert your IRA?)

Model a Roth conversion vs waiting. Adjust tax rates, payment source, and time horizon to compare outcomes. What-if tool for planning.

Your inputs

About this calculator

Compare paying tax now on a conversion vs keeping money in a pre-tax IRA.

Your information

Enter your best estimates below.

Total pre-tax IRA balance before converting.
Money you already paid tax on inside the IRA — lowers taxable conversion.
How much you move to Roth this year.
Years until you need the money — more time for Roth growth to matter.
Paying tax from outside the IRA leaves more in Roth; paying from the conversion reduces what converts.

How we run the estimate

Change return, inflation, and tax rates below. IRA amounts and how you pay tax stay in the panel above.

Growth on remaining IRA and Roth balances.
6.0%
Adjusts future values to today’s dollars.
3.0%
Federal rate on the conversion this year.
Federal rate assumed when you withdraw later.
Mixed IRA money
After-tax basis reduces the taxable part of the conversion using IRS mixed-balance rules
Tax scope
Federal income tax only — state taxes are not included
Paying tax from outside the IRA
Outside money for taxes grows at 5% per year until withdrawal (simplified)

Your results

Convert now looks better

What it means

Converting now is projected to leave you with more after-tax money at the end of the period you chose.

How we chose it

We compare growing a Roth after paying conversion tax today with keeping a traditional IRA and paying tax on withdrawals later, using your tax rates and return.

Future value if you convert

$210K

vs $110,408 if you don't convert. Difference: $99,291 ($63,731 in today's dollars).

Tax due now

$11,000

Difference (today's dollars)

$63,731

Convert vs. don't convert over time

  • If you convert
  • If you do not convert
123456789101112131415Year$0$55K$110K$165K$220K

Beyond this calculator

Roth conversions are usually planned across several years

This comparison looks at a one-time conversion with simplified taxes. A complete Retirelens plan also models:

  • Staggered conversions to stay in lower tax brackets
  • Medicare premium surcharges from a spike in taxable income
  • State tax and after-tax dollars available to pay the conversion tax
  • Inherited-account rules and beneficiary priorities

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Interpretation

What this means

Planning context for the estimates above. Not tax, legal, or investment advice.

Converting $50,000 now at 22% federal costs $11,000 in tax today. If future rates reach 25%, converting now comes out ahead by $99,291.

Spreading conversions over low-income years is often the optimal strategy — this model compares one conversion amount only.

Methodology

How this calculator works

The rules and math behind this estimate.

The "convert" path moves the target amount to a Roth account (net of tax if paying from conversion, or the full amount if paying from outside funds). The remaining pre-tax IRA and the Roth account both grow at the selected annual return.

The "no convert" path keeps the full amount in a Traditional IRA growing at the same rate. At withdrawal, the future tax rate is applied. The after-tax values at the end of the horizon are compared.

Help

Frequently asked questions

Straight answers to common questions about this calculator.

Should I convert my IRA to Roth?

It can make sense if you pay tax now at a lower rate than you expect later, or you want tax-free withdrawals and less forced withdrawals later. It may not make sense if it pushes you into a much higher tax bracket.

How much tax will I owe?

The amount you convert is usually added to your taxable income that year and taxed at your normal rates.

Can conversion raise Medicare costs?

Yes. Very high income can raise Medicare Part B and D premiums two years later. This tool flags that so you can plan smaller conversions.

Should I pay tax from savings outside the IRA?

Often yes — paying tax from a non-retirement account lets more money stay in the Roth growing tax-free.

Your full retirement picture

Retirement is more than money

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A good retirement plan covers money, health, how you spend your time, people you care about, and what you pass on. That is how Retirelens looks at the full picture.

Finance

Know where you stand and what to do next with your money.

74% of planners reported satisfaction with retirement income vs. 43% of non-planners (Goldman Sachs)

Health

Secure solid coverage, stay ahead with preventive care and healthy habits a staple.

68% of adults ages 50–64 said they were concerned that federal policy changes could affect their health insurance coverage. (University of Michigan)

Purpose

Shape days you look forward to, with steps to get there.

Research shows that a stronger sense of purpose is associated with lower mortality risk among adults over age 50. (American Medical Association)

Connections

Strengthen relationships and build a support circle.

A longitudinal study of adults aged 65+ found that older adults with more diverse social networks had a lower risk of death and better cognitive and physical function than those with less diverse networks. (Chico Health Aging Project)

Legacy

Organize your assets and document so your family isn't left guessing.

Without a proper estate plan, more than half of families experience disputes or have assets end up under court control. (LegalShield)