Most people don't understand what they're actually deciding. This walks you through every number — tax brackets, IRMAA, Social Security, RMDs, and what your heirs face — so you can decide with confidence, not guesswork.
IRMAA-aware
State tax included
Social Security integration
SECURE Act 10-year rule
Multi-year scenarios
Is this calculator for you?
A Roth conversion moves money from a Traditional IRA or 401k (where you paid no income tax going in, but owe tax coming out) into a Roth IRA (where you pay tax now, and everything grows and exits completely tax-free).
You should consider this if any of these describe you:
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You have 5–15 years until retirement
Pre-RMD window is the golden period for conversions — you have control over your income.
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You expect higher future tax rates
Tax cuts from 2017 may expire in 2026. If you think rates go up, pay taxes now at lower rates.
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Your Traditional IRA is $200K+
Larger accounts create larger future RMDs — mandatory withdrawals that push your income up for life.
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You're leaving an IRA to heirs
Non-spouse heirs must empty a Traditional IRA in 10 years — and pay income tax on every dollar. Roth = zero tax to them.
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You want to control Medicare costs
IRMAA is the income-driven Medicare surcharge. High RMDs can push you into higher tiers for a decade-plus.
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You already have a Roth and want to balance
Mixing pre-tax and Roth gives flexibility in retirement — you control which bucket to draw from based on the year.
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Tell us about yourself
Age, filing status, state, income
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Add your IRA
Balance and conversion amount
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See 4 scenarios
Recommended, aggressive, conservative, none
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Understand every cost
Taxes, IRMAA, SS impact, RMDs
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Know exactly what to do
Step-by-step next actions
Plain English, always. This calculator never assumes you know what a "bracket" or "IRMAA" or "RMD" means. Every term is explained the moment it appears. No jargon.
⚠️ When a Roth conversion might not be right
You're in a high tax bracket now and expect to be in a similar or lower one in retirement. If you're already at 32%+ marginal rate, the math is tighter — weigh it carefully.
You need the money within 5 years. Converted funds are locked for 5 years (the 5-year rule) unless you're 59½ or older. Don't convert emergency fund money.
You can't pay the conversion taxes from outside the IRA. If you convert $30K but owe $7K in taxes and don't have cash to pay it, the IRS treats the unpaid tax as an additional conversion — creating a spiral.
You're very close to retirement and already drawing Social Security. Conversions after SS starts stack on top and can significantly increase how much of your SS is taxed.
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You
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Income
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IRA
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Goals
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Results
Tell us about yourself
This shapes your tax brackets, your IRMAA thresholds, and when Social Security becomes a factor.
Why filing status matters: The IRS uses completely different tax brackets for single filers vs. married filing jointly. Your filing status also sets your IRMAA thresholds — the income levels that determine your Medicare Part B & D premiums.
30 — 8560
📖 What Is a Roth Conversion? (Plain English)
You have money in a Traditional IRA or 401k. You never paid income tax on those dollars going in — the IRS will collect when you withdraw.
A Roth conversion moves money from that pre-tax account into a Roth IRA. You pay income tax now, at today's rates, and the money then grows tax-free — forever, and for your heirs too.
The core question is: Will your tax rate in retirement be higher or lower than today? If higher (or you're unsure), converting at today's rates makes sense — especially since current tax rates are near historic lows.
There's no limit on how much you can convert. But every dollar converted is added to your taxable income for that year.
Once in the Roth, never taxed again — not for income tax, not for IRMAA (partly), and not for your heirs under the SECURE Act.
📖 The 5-Year Rule — Don't Get Caught
Earnings in a Roth IRA must be in the account at least 5 years before withdrawal. This clock starts when you first fund any Roth IRA, regardless of age.
Converted funds have their own separate 5-year clock — each calendar year of conversion is tracked independently.
If you're 59½ or older, you can withdraw converted funds immediately without the 10% early withdrawal penalty. The earnings still need their own 5-year window.
Strategy: Start converting 5+ years before you expect to need the money. Every dollar then has its own penalty-free window.
Your income picture
We need your expected annual income — before any Roth conversion — to calculate your exact tax brackets and IRMAA tier.
⚠️ Critical: The 2-year IRMAA lag. Income you earn in 2026 determines your Medicare Part B & D premiums in 2028. A Roth conversion this year increases your 2028 Medicare costs. This lag is the #1 thing people miss when planning conversions.
$20K — $500K$75,000
📖 How Tax Brackets Actually Work (Most People Get This Wrong)
Tax brackets are marginal — only income above each threshold is taxed at the higher rate. If you're single with $80K income, only dollars above $47,725 are taxed at 22% — not your whole $80K.
A Roth conversion adds on top of all your other income. It fills brackets from the bottom up — just like a paycheck.
Key strategy: Stop converting once you reach the top of a lower bracket (22% or 24%). Don't push into 32%+ territory unless you have a specific reason.
The effective tax rate (total tax ÷ total income) is always much lower than the marginal rate (rate on the last dollar). This calculator shows both.
📖 Social Security + Roth Conversions: The Hidden Interaction
Up to 85% of your Social Security benefits can be taxed as ordinary income, based on your other income.
The IRS calculates this using provisional income: your non-SS income plus 50% of your SS benefits. If this exceeds certain thresholds, SS becomes taxable.
A Roth conversion increases your provisional income — potentially making more of your Social Security taxable. A double tax hit.
The optimal window: Convert before you start Social Security. Pre-SS conversions don't stack on top of SS income. Once SS starts, conversions can significantly increase your SS tax burden.
The right strategy: Maximize Roth conversions in your early 60s before SS starts. Then adjust once SS begins.
Your IRA and how much to convert
Tell us how much is in your Traditional IRA and how much you're considering converting each year.
$10K — $3M$300,000
$0 — $200K$30,000
0% — 12%5.0%
How a conversion works: You call your IRA custodian (Fidelity: 800-343-3548, Schwab: 800-435-4000, Vanguard: 800-662-2739) and request a Roth conversion. You specify the dollar amount to move from your Traditional IRA → Roth IRA. The custodian reports the amount as ordinary income. You get a 1099-R at tax time. The money then grows tax-free, forever.
📖 RMDs — The Silent Tax Force You're Probably Ignoring
Required Minimum Distributions (RMDs) start at age 73 (born 1951 or later). The IRS forces you to withdraw a minimum amount from your Traditional IRA every year — and every dollar is taxed as ordinary income.
RMDs are calculated as: IRA balance ÷ IRS life expectancy factor. As your IRA grows, your RMDs grow — and so does your tax bill. And those RMDs push your income up, which can raise your IRMAA premiums too.
Why this matters for conversions: Roth conversions done before age 73 reduce your IRA balance, which shrinks future RMDs. Every dollar converted before RMDs start = smaller RMDs later = less forced taxable income.
If you wait until after RMDs start, you're playing catch-up. Mandatory withdrawals may push you into higher brackets — and your flexibility to convert strategically is dramatically reduced.
The math: If you have $500K in a Traditional IRA at age 73, your first RMD is ~$18,248 (at 27.4 factor). That's taxable income. If you're already drawing Social Security, that RMD could make 50% of your SS taxable — and push you into a higher IRMAA tier.
Your conversion goals
This helps us choose the right scenario for your situation and explain the reasoning clearly.
✓ Quick knowledge drop: Converting is most powerful when (1) you're in a lower bracket now than you'll be in retirement, (2) you're before age 73 and can manage your IRA balance, and (3) you want to reduce the tax burden on yourself and your heirs in the future.
📖 What Is IRMAA — and Why It Could Cost You $30,000+ Over a Lifetime
IRMAA = Income-Related Monthly Adjustment Amount. It's the extra you pay each month for Medicare Part B (doctor/outpatient care) and Part D (prescription drug plan), based on your income.
The base premium is $174.70/month (2026). But if your MAGI exceeds $103,000 (single) or $206,000 (married filing jointly), you pay an additional $115–$568/month on top of that.
IRMAA is based on your income from 2 years prior. Income in 2026 affects Medicare premiums in 2028. That's the lag you must plan around.
The trap: RMDs from a Traditional IRA are mandatory and count as income. Once you trigger a higher IRMAA tier, you stay there until your income drops below a threshold for 2 straight years. With mandatory RMDs, that's nearly impossible.
The opportunity: Converting in your early-to-mid 60s — before RMDs start — can keep your IRA balance low enough that IRMAA stays manageable for the rest of your life. The savings can exceed $30,000 over 20 years.
📖 The SECURE Act 2.0 and Your Beneficiaries — The 10-Year Rule
If you leave a Traditional IRA to a non-spouse beneficiary (adult child, grandchild), they must withdraw all funds within 10 years under the SECURE Act. Every dollar is taxed as ordinary income — potentially at 32–37%.
A Roth IRA left to heirs is also subject to the 10-year rule — but all distributions are completely tax-free. The same $300,000 IRA becomes zero tax to heirs if it's a Roth, vs. $96,000+ in taxes if it's Traditional.
For a beneficiary in a high tax bracket, inheriting a Traditional IRA can be financially devastating. A Roth conversion solves this at the source.
Note: Spouse beneficiaries can always stretch Traditional IRAs over their lifetime. Non-spouse beneficiaries cannot — they get the 10-year rule, and it applies to both Traditional and Roth accounts.
The SECURE Act 2.0 also changed some rules around RMD age (now 73) and catch-up contributions — this calculator uses the current rules.
📖 Why the Next 7 Years Are Critical — Tax Cuts Sunset in 2026
The Tax Cuts and Jobs Act of 2017 significantly lowered income tax rates. Most of these cuts are scheduled to expire after December 31, 2025.
If Congress doesn't extend the cuts, tax rates revert to pre-2017 levels in 2026 — meaning your 22% bracket could become 25%, your 24% could become 33%, etc.
This means 2026 could be the last chance to convert at historically low rates. Every dollar you convert in 2025 or 2026 is taxed at today's rates — before potential increases.
Year-end planning matters. December conversions are often better than January — the converted funds have less time exposed in the market before a potential rate increase, and you lock in the current year's rates.
If rates do go up significantly in 2026, doing a large conversion in late 2025 (before the change) could save tens of thousands in taxes over a multi-year plan.
Disclaimer: This calculator is for educational and planning purposes only. It does not constitute financial, tax, legal, or Medicare advice. Tax laws, IRMAA thresholds, and Medicare premiums are subject to annual change. All calculations use 2026 IRS tax brackets and 2026 IRMAA tiers. Actual results will vary. For personalized guidance, consult a licensed CPA, CFP, or financial advisor. Defying Logic is not a financial services company.