Roth Conversion & Backdoor Roth Calculator

Roth conversion & backdoor Roth calculator

Estimate standard conversion tax cost, or plan a backdoor Roth strategy with pro-rata analysis and income limit checks.

Calculator mode *

Filing status *

Current taxable income *

Use taxable income after deductions, not gross salary.

Conversion amount

Standard mode only. The amount to convert from traditional to Roth.

Expected future withdrawal tax rate (%)

Standard mode only.

Years until withdrawal

Standard mode only.

Modified adjusted gross income (MAGI)

Backdoor mode only. Used to check Roth IRA income eligibility.

Existing traditional IRA balance (pre-tax)

Backdoor mode only. Pre-tax IRA funds trigger the pro-rata rule. Enter 0 if you have no pre-tax IRA money.

Nondeductible contribution amount

Backdoor mode only. The after-tax amount you contribute to a traditional IRA before converting. 2026 limit: $7,000 ($8,000 if 50+).

Years to project

Backdoor mode only. How many years of annual backdoor contributions to project.

State tax rate (%) *

Expected annual growth (%) *

All required fields must be filled in.

Conversion Analysis

Choose Standard mode for a lump conversion analysis, or Backdoor mode for high-income Roth IRA planning with pro-rata impact.

Calculation History(0)

No calculations yet. Complete a calculation to see it here.

Tap an example to prefill the calculator with sample values.

Mid-career partial conversion

$50k conversion at a 24% federal bracket edge

Useful for seeing whether today's tax cost is low enough relative to a lower future retirement tax rate.

Result: A moderate upfront tax hit can still create a five-figure long-run after-tax edge if retirement tax rates stay lower

Backdoor Roth — clean (no pre-tax IRA)

High earner with $200K MAGI, no existing traditional IRA

The ideal backdoor scenario: no pre-tax IRA balance means the pro-rata rule has zero impact. The full contribution converts tax-free.

Result: $7,000 converts tax-free each year — $0 tax impact because there's no pre-tax IRA balance

Backdoor Roth — pro-rata trap

High earner with $50K in an old rollover IRA

The pro-rata rule makes most of each backdoor conversion taxable when pre-tax IRA funds exist. Consider rolling into a 401(k) first.

Result: With $50K pre-tax IRA, ~87% of each conversion is taxable — the pro-rata rule significantly reduces the backdoor benefit