Sources: IRS, SEC, Federal Reserve, U.S. Bureau of Labor Statistics & U.S. Census Bureau. See our editorial standards.
Free Roth conversion calculator. See the exact tax you'll owe to convert your Traditional IRA in 2026, plus break-even age and bracket-fill strategy.
A Roth conversion moves money from a traditional (pre-tax) IRA or 401(k) into a Roth IRA, and you pay ordinary income tax on every dollar converted in the year you do it. If you convert $50,000 and you're in the 22% federal bracket, you owe roughly $11,000 in federal tax that April — but every dollar then grows tax-free and comes out tax-free in retirement, with no required minimum distributions. The entire decision hinges on one question: will your tax rate in retirement be higher or lower than it is today? Convert when your current rate is lower, and you win. This calculator and guide show you exactly how to run those numbers, what your break-even year looks like, and the traps that quietly inflate the bill.
Plug in your numbers to estimate the immediate tax cost and the long-term payoff. The math below mirrors what the interactive tool computes.
| Input | Example value |
|---|---|
| Amount to convert | $50,000 |
| Current taxable income (before conversion) | $90,000 (MFJ) |
| Current marginal federal bracket | 22% |
| State income tax rate | 5% |
| Years until withdrawal | 20 |
| Expected annual return | 7% |
| Expected retirement tax bracket | 24% |
How to read your result: The calculator returns three numbers that matter — your conversion tax bill (what you owe now), your break-even year (when tax-free growth has repaid that bill), and your lifetime tax savings (the projected difference versus leaving the money in a traditional account). If your break-even lands before your expected withdrawal date and your retirement bracket is equal to or higher than today's, the conversion is mathematically favorable.
The converted amount stacks on top of your existing taxable income, which is the single most misunderstood part of the process. Converting $50,000 doesn't get taxed at a flat 22% — it can spill into higher brackets.
Here are the 2026 federal brackets for married filing jointly:
Worked example. A couple has $90,000 of taxable income and converts $50,000. After the $30,000 standard deduction, their taxable base is already in the 12% band. The first $6,950 of the conversion fills the rest of the 12% bracket ($96,950 − $90,000), taxed at 12% = $834. The remaining $43,050 is taxed at 22% = $9,471. Federal tax on the conversion: $10,305. Add 5% state tax ($2,500) and the all-in cost is $12,805 — an effective rate of 25.6%, not the 22% headline bracket. This bracket-spillover effect is why splitting a large conversion across multiple years almost always beats doing it in one shot.
The break-even is the point where the tax-free compounding inside the Roth has grown enough to offset the tax you paid up front. The cleaner the comparison, the more important one rule becomes: pay the conversion tax from outside money (a savings or brokerage account), not from the converted funds.
If you pay the tax out of the conversion itself, you're shrinking the Roth balance and effectively converting less. Paying from outside cash means the full $50,000 keeps compounding. At 7% annual growth, $50,000 becomes roughly $193,500 in 20 years — all tax-free. The same $50,000 left in a traditional IRA also grows to $193,500, but withdrawals get taxed. At a 24% retirement rate, that's about $46,400 in future tax versus the $12,805 you paid now. The break-even in this scenario arrives around year 7–9, after which the Roth pulls decisively ahead. You can sanity-check the growth side of this with our compound interest calculator.
The federal income tax is the obvious line item. These are the ones that ambush people:
If you're 63 or older, a large conversion can spike your modified adjusted gross income and trigger higher Medicare Part B and D premiums two years later. In 2026, crossing the first IRMAA threshold (around $109,000 single / $218,000 joint MAGI) adds roughly $840 per person per year in Part B surcharges alone. Conversions done before age 63 sidestep this entirely.
Extra income from a conversion can push more of your Social Security benefits into the taxable column — up to 85% of benefits become taxable at higher income levels. If you're already drawing benefits, model this carefully; see how the thresholds work in our Social Security tax calculator.
Each conversion starts its own five-year clock. Withdraw the converted principal before five years have passed (and before age 59½) and you may owe a 10% penalty on it. This rarely matters for long-term planners but is critical if you're converting in your late 50s and might need the cash soon.
The ideal window is a "gap year" — a period when your income temporarily drops and your marginal rate falls. Common triggers:
Conversions backfire in predictable situations. Skip or delay if: you'd have to pay the tax from the converted funds; you expect a lower tax bracket in retirement (common for high earners who'll downshift); you're 63+ and near an IRMAA cliff; you need the money within five years; or the conversion would push you from the 22% into the 32% bracket in a single year. In that last case, splitting the conversion across three or four years keeps you in the lower band and can save thousands. Households weighing a big asset sale alongside a conversion should also check the capital gains tax calculator, since stacked income events compound the bracket problem.
For a $200,000 traditional IRA, a "bracket-filling" approach usually beats a lump conversion. Suppose a retired couple has $40,000 of other taxable income. The top of the 12% bracket sits near $97,000, leaving about $57,000 of headroom each year at the 12% rate. Converting $57,000 annually for roughly four years moves the entire $200,000 while keeping every converted dollar taxed at just 12% — versus a one-year conversion that would push tens of thousands into the 22% and 24% bands. Over four years, that disciplined approach can cut the total conversion tax by $15,000–$25,000 on a balance this size.
This content is for educational purposes only and does not constitute financial advice. Tax rules change and individual situations vary — consult a qualified financial advisor or CPA before executing a Roth conversion.
You pay ordinary income tax on the full converted amount at your marginal rate, and the conversion stacks on top of your existing income. A $50,000 conversion for someone in the 22% bracket typically costs $10,000–$11,000 federally, plus state tax. Because the amount can spill into a higher bracket, your effective rate is often a few points above your headline bracket — run your exact figures through the calculator above.
No. Unlike direct Roth IRA contributions, which phase out at higher incomes, Roth conversions have no income cap. This is the basis of the "backdoor Roth" strategy, where high earners contribute to a traditional IRA and immediately convert it. Anyone with a traditional IRA or eligible 401(k) can convert any amount.
Always pay from outside savings if you can. Using IRA funds to cover the tax shrinks the amount that grows tax-free and, if you're under 59½, may trigger a 10% penalty on the withheld portion. Paying from a brokerage or savings account keeps the entire converted balance compounding inside the Roth, which is what drives the long-term advantage.
No. The Tax Cuts and Jobs Act eliminated "recharacterization" of conversions starting in 2018. Once you convert, it's permanent for that tax year, so the decision must be right before you pull the trigger. This is exactly why modeling the tax cost and break-even in advance matters so much.
The sweet spot for most people is the "gap years" between retiring (often early-to-mid 60s) and when RMDs and Social Security begin. Income is typically low during this window, so conversions are cheap, and completing them before age 63 also avoids triggering IRMAA Medicare surcharges. Younger savers in a low bracket today who expect higher rates later are also strong candidates.
The content on this page is for informational purposes only and should not be considered financial advice. Rates, terms, and offers are subject to change. We may earn a commission through affiliate links at no extra cost to you. See our full disclaimer.
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