Roth Conversion Calculator
See exactly what a conversion costs, which brackets it fills, and how much room you have left before the next rate — the number that decides how much to convert.
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Quick Answer
A Roth conversion is taxed as ordinary income in the year you convert — no penalty, no special rate. The entire game is where the conversion lands in your brackets: convert enough to fill your current bracket, stop before the next one, repeat annually. This calculator shows the slices, the total cost, and the headroom — the same bracket-fill math behind every conversion plan we build.
Your Numbers
Pre-tax IRA / 401(k) dollars moving to Roth this year.
Wages, business, pension, taxable interest — before this conversion.
Converting before a move to a no-tax state? That's a timing play.
Enter a conversion amount above to see the breakdown.
Bracket-Fill: How Smart Conversions Are Sized
Every conversion is a bet that today's rate beats tomorrow's. Since the converted dollars stack on top of your other income, the smart play is rarely "convert everything" — it's convert exactly enough to fill the bracket you're comfortable paying, every year, until the pre-tax balance is where you want it. A retiree with $60,000 of income might fill the 22% bracket annually for a decade rather than face 32%+ RMD-driven rates at 75.
The multi-year version is the Roth conversion ladder: a planned sequence of annual conversions, each sized to a target bracket. Early retirees add a second motive — each year's conversion becomes penalty-free accessible after its own five-year clock, creating a rolling pipeline of spendable funds before 59½. Ladders interact with everything: estimated payments (each conversion year needs a payment plan), ACA premium credits, IRMAA at 63+, and the 0% capital gains bracket you might be filling with the same room.
Still working and high-income? The conversion math connects to two cousins worth knowing: the backdoor Roth IRA (small annual conversions that route around the income limits) and the mega backdoor Roth (after-tax 401(k) dollars converted at near-zero tax cost).
Market dips are conversion sales
Converting 1,000 shares at $80 instead of $120 moves the same future recovery into the Roth for 33% less tax. Volatile years are when conversion plans earn their keep — but only if the plan exists before the dip shows up.
Common Questions
Build the ten-year conversion plan
We map your brackets from now through RMDs, size each year's conversion, and handle the estimated payments so the plan doesn't create penalties. One free call to see your window.
Find Out What You're Overpaying in Taxes
Book a free 30-minute call to walk through your situation. We'll tell you exactly how our CPA-led team can help — and whether we're the right fit.