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💜 Retirement · Tax Strategy · Free

Roth Conversion Calculator

Should you convert your Traditional IRA or 401(k) to a Roth in 2026? Enter your balances, current vs. retirement tax bracket, and a multi-year conversion ladder to see the lifetime tax savings of Path A (convert) vs. Path B (don't).

Your Balances

Used to determine years to retirement and time horizon for tax-free Roth growth.

Conversion Ladder Plan

Amount to convert each year for the duration of the ladder. Aim to "fill up" your current bracket without spilling into the next one.
Most planners spread conversions over 5-15 years to bracket-fit.
Historical 60/40 portfolio average: 7-8%. Use 6% for conservative modeling.

Tax Brackets

Wages, interest, dividends, pension — everything except the conversion itself. Used to find your current marginal bracket.
Social Security + RMD + other income in retirement. Compare this to current income to size the benefit.

How the Conversion Math Works

A Roth conversion moves dollars from a Traditional (pre-tax) account into a Roth (post-tax) account. The full converted amount is added to your taxable income in the year of the conversion. In exchange, all future growth and qualified withdrawals from the Roth are completely tax-free — and there's no Required Minimum Distribution at age 73 or 75 for the original owner.

The break-even math: if you expect your future tax rate to be equal to your current rate, conversion is roughly a wash on a lifetime basis (you pay tax now instead of later on the same dollars). Conversion wins decisively when:

This calculator runs both Path A (convert over a ladder) and Path B (don't convert, take RMDs and withdraw as needed in retirement), accounting for federal + state marginal brackets each year, then gives you the lifetime tax cost and benefit.

Frequently Asked Questions

What is a Roth conversion?

A Roth conversion is when you move money from a tax-deferred retirement account (Traditional IRA, Traditional 401(k), 403(b)) into a Roth IRA. The transferred amount is added to your taxable income for the year of the conversion, but all future growth and qualified withdrawals from the Roth are tax-free. There's no income limit on conversions and no required minimum distributions on Roth IRAs during the original owner's lifetime.

When is a Roth conversion a good idea?

A Roth conversion usually makes sense when you expect your future tax rate to be higher than today's. The most common cases: (1) you have a low-income gap year between retirement and Required Minimum Distributions (RMDs), (2) you expect tax rates to rise (look at current budget deficits), (3) you want to leave tax-free money to heirs, (4) you have moved to a higher-tax state and are converting in a lower-tax one. The math compares your current marginal bracket to your expected retirement bracket.

How much can I convert to Roth per year?

There is no IRS-imposed annual cap on Roth conversions — you can convert any amount in any year. The full converted amount is added to your ordinary taxable income for that year, however, so large conversions can push you into a higher federal and state tax bracket. The pro-rata rule does NOT apply to conversions (only to backdoor Roth contributions), so you can convert from a Traditional IRA with pre-tax money regardless of your other IRA balances.

What is the Roth conversion 5-year rule?

Each Roth conversion has its own 5-year clock. If you withdraw the converted amount before age 59½ AND before the 5-year anniversary of the conversion, the 10% early-withdrawal penalty applies to the converted amount (the earnings portion is always penalty-free if you meet the qualified-distribution rules). After 5 years AND age 59½, the entire balance — both contributions and earnings — can be withdrawn with no tax and no penalty.

Will I owe taxes on my Social Security if I do a Roth conversion?

Yes — large Roth conversions often push you above the Social Security taxable-income thresholds, causing up to 85% of your benefits to become taxable. This "tax torpedo" effect means $1 of conversion can trigger $0.15-$0.50 of additional Social Security tax. The calculator does not model this in detail, but if you are within 5 years of claiming Social Security, factor in roughly 15% additional tax on your conversion when the timing matters.

Should I do a Roth conversion in a down market?

Yes — converting in a down market is one of the most powerful strategies because you buy more shares with each dollar of tax cost. Example: if your Traditional IRA balance drops 30% in a bear market, you can convert $100,000 worth of depressed shares that recover to $200,000+ by retirement, all tax-free, while the tax cost was based on the lower $100,000 balance. Many planners suggest "buy low" during downturns and pause conversions near market peaks.

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