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Roth Conversion Multi-Year Planner

Estimate the current federal tax cost, then follow the converted dollars year by year against a no-conversion scenario that keeps future traditional tax and tax-payment opportunity cost visible.

Planning boundary: This calculator uses federal ordinary-income bracket math and a simplified projection. It does not calculate state taxes, Social Security taxation, ACA subsidies, IRMAA thresholds, capital-gains interactions, tax credits, AMT, NIIT, estate planning, or an actual tax return.

Inputs

Conversion assumptions

Plan name

Tax table Filing status

Ordinary taxable income before conversion Use taxable ordinary income after deductions, not gross income. Traditional IRA dollars included in this decision If tax is paid from outside funds, this amount reaches Roth. If tax is withheld, only the net reaches Roth. Taxable percentage of the conversion Use 100% unless you know your IRA basis/pro-rata calculation.

Bracket-fill target

How will the conversion tax be paid? Outside funds Full conversion reaches Roth, but the tax payment loses its own future growth. From conversion funds Tax withholding reduces what lands in Roth and may create penalty issues if you are under 59 1/2.

Years to compare Expected annual return

Assumed future tax rate on traditional withdrawals This simplified model applies one future tax rate to the traditional balance in every projected year.

Show warning messages when these may apply I am on Medicare now, or could be within the income lookback window. I am subject to required minimum distributions for this tax year. I am under age 59 1/2.

Step 1

Current-year setup

Incremental federal tax $0

Effective tax on taxable conversion 0%

Amount reaching Roth $0

Tax-payment opportunity value $0

Step 2

Year-by-year comparison

No conversion vs Roth conversion

Enter assumptions to compare scenarios.

Crossover pending

Tax payment reality check

The tax payment is counted.

Year 1 before future-tax estimate $0

Year 1 estimated traditional tax $0

Year 1 after-tax comparison $0

Final Roth value $0

Final no-conversion after-tax value $0

Final traditional tax drag $0

Final tax-payment opportunity value $0

Final after-tax conversion ahead/behind $0

Year	Roth value	Traditional value	Estimated traditional tax	Tax payment opportunity value	No-conversion after-tax value	After-tax ahead/behind

Step 3

Conversion amount scenarios

Bracket fill

Where the conversion lands

Rate	Conversion dollars in bracket	Tax

Heads-up messages

Not modeled, but potentially important

Method summary

The tax bill is only the first line.

No-conversion scenario

The traditional IRA dollars remain traditional, grow at the entered return, and are reduced by the assumed future tax rate when compared as after-tax value. When taxes would have been paid from outside funds, those outside dollars remain invested in the no-conversion scenario.

Roth conversion scenario

The converted amount grows as Roth money. If taxes are paid from outside funds, the full conversion reaches Roth but the tax payment still has a future opportunity value. If taxes are withheld from the conversion, the amount reaching Roth is lower.

The projection uses one return assumption and one future traditional-withdrawal tax rate. It is designed for educational comparison, not tax preparation or personalized advice.