Roth Conversion Calculator 2025 β Tax Cost vs Future Savings
Calculate whether a Roth conversion makes sense. See the tax cost now vs tax savings later and find your breakeven year.
Conversion Analysis
How to Use This Roth Conversion Calculator
Enter the amount you want to convert, your current tax bracket (the rate at which the conversion will be taxed), and your expected retirement tax rate. The calculator compares the immediate tax cost against the future tax savings on the grown balance to determine if the conversion is worthwhile.
For best results, pay the conversion taxes from outside funds (not the converted amount), so the full converted amount grows in the Roth.
The Formula
Future Value = Conversion Amount Γ (1 + r)^n
Tax Saved Later = Future Value Γ Retirement Rate
Net Benefit = Tax Saved Later β Tax Cost Now (FV-adjusted)
Breakeven: Year when cumulative benefit > tax cost
Example
Tax cost now: $50,000 Γ 22% = $11,000
Future value in Roth: $50,000 Γ (1.07)^20 = $193,484
Tax avoided: $193,484 Γ 18% = $34,827
Net benefit: $34,827 β $11,000 = $23,827 β Conversion is worthwhile!
Optimal Conversion Amount Analyzer
Find the ideal conversion amount to fill your current tax bracket without jumping into a higher one
Find the optimal conversion amount β the maximum you can convert without entering the next tax bracket.
Bracket Fill Analysis β How Much Can You Convert at Each Rate?
| Tax Bracket | Room Available | Tax on Conversion | Future Value (20yr) | Recommendation |
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