A step-by-step interactive tool to minimise your lifetime tax burden through smart Roth IRA conversion strategies — with IRMAA guardrails, ACA cliff awareness, and an AI-powered tax rate updater. All in a single self-contained HTML file.
You have a traditional IRA or 401(k) with decades of pre-tax growth. Starting at age 73, the IRS will require you to withdraw a portion every year as a Required Minimum Distribution (RMD) — and every dollar withdrawn is taxed as ordinary income. If your IRA is substantial, RMDs can push you into higher tax brackets, trigger Medicare premium surcharges (IRMAA), and cost you tens or hundreds of thousands in unnecessary lifetime taxes.
Roth IRA conversions let you move money from your traditional IRA to a Roth account, paying tax at today's rates on the converted amount. Once in the Roth, that money grows tax-free forever and never counts toward RMDs. The challenge is knowing how much to convert, in which years, and which tax cliffs to avoid — get it wrong and you could trigger IRMAA surcharges, lose ACA subsidies, or pay more in taxes than you save.
7 steps to a confident plan
Starting Point Enter your age, IRA and Roth balances, Social Security estimate, retirement spending goal, and annual IRA withdrawals. The tool instantly calibrates your current tax position.
The Problem See the "Tax Torpedo" — a visualisation of how RMDs will stack your future income into higher brackets. You'll see the projected RMD schedule from age 73 onward and your effective marginal rate at the start of RMDs.
The Opportunity Your conversion window — the years before RMDs begin. The tool shows how much 12% and 22% bracket space is available each year, with red markers for IRMAA cliffs and purple markers for ACA cliffs.
The Guardrails Interactive IRMAA and ACA cliff exploration. Adjust a slider to see exactly where your MAGI sits relative to IRMAA surcharge tiers and the ACA 400% FPL cliff — in real time.
Your Plan Choose from six conversion strategies and see a year-by-year conversion calendar with tax cost, bracket used, and Roth balance projection. Switch strategies and the numbers update instantly.
Verify Compare all six strategies side by side. See total conversions, lifetime tax savings, Roth balance at 73, and estate value gain. Pick the strategy that fits your goals.
Confidence & Action Six confidence checks verify your plan against tax torpedoes, IRMAA thresholds, ACA cliffs, RMD reduction, lifetime tax improvement, and estate value. Print your personalised action plan with the conversion calendar and tax verification date stamp.
Five conversion strategies, one clear winner
Each strategy is simulated year-by-year from your current age through your life expectancy. The tool compares them all so you can see which approach maximises your after-tax lifetime wealth.
What makes this different from every other Roth calculator
It's a 7-step wizard, not a one-shot calculator. Most Roth tools give you a single number. This one walks you through the problem, the opportunity, the guardrails, and the strategy — building understanding at every step.
IRMAA guardrails built in. Medicare premium surcharges (IRMAA) can add thousands per year to your costs if your MAGI exceeds certain thresholds. The Optimizer shows you exactly where each threshold sits and warns you before you cross it. Most consumer tools ignore IRMAA entirely.
ACA cliff awareness for pre-65 retirees. If you're using ACA marketplace health insurance before Medicare, a conversion that pushes your MAGI over 400% FPL can cost you thousands in lost subsidies. The Optimizer flags this on every step.
AI-powered tax rate updates. Tax brackets change every year. Instead of shipping outdated rates, the tool includes an AI prompt that lets you fetch current-year figures from any AI assistant (Claude, ChatGPT, Gemini) and apply them in one click. No manual lookup required.
Five strategies compared side by side. Not just a recommendation — you see the actual numbers for every approach. Total conversions, lifetime tax saving, Roth balance at 73, and estate value gain for all six.
Printable action plan with confidence score. Step 7 gives you a confidence-checked, date-stamped summary you can print, share with your advisor, or keep as a record of your reasoning.
Fully offline, fully private. One HTML file. No installation. No account. No data sent anywhere. Your financial information stays on your computer.
Exports to the companion Retirement Income Planner. Your chosen conversion schedule can be exported as a `.roth-plan.json` file and imported directly into the separate AI-Ready Retirement Income Planner — the two tools work together seamlessly.
How this compares to other Roth tools
Professional Roth conversion software costs $109–$200+/month. Free online calculators give you a single number with no strategy. This tool is the middle ground that DIY retirees have been missing.
Tax Torpedo visualisation See exactly how RMDs will push your future income into higher brackets with an interactive SVG chart.
RMD schedule projection Year-by-year RMD amounts from age 73 onward, colour-coded green/amber/red by severity.
Conversion window timeline Available 12% and 22% bracket space shown as timeline bars for each year before RMDs begin.
IRMAA thermometer Live visual of your MAGI position relative to all 5 IRMAA surcharge tiers with the 2-year lookback rule.
ACA cliff detection Pre-65 years flagged with 400% FPL markers to protect your marketplace subsidies.
Year-by-year conversion calendar Age, base income, conversion amount, tax cost, bracket used, and Roth balance for every year in the conversion window.
Portfolio trajectory chart SVG line chart comparing IRA vs Roth balance over time, with no-conversion baseline overlay.
AI tax rate import One-click copy of a structured prompt — paste into any AI assistant, then paste the response back to auto-fill all tax parameters.
Tax staleness detection Amber banner alerts you when the built-in tax rates are from a previous year. Dismiss once reviewed.
Verification date stamp Click "Mark as Verified" to stamp your plan with today's date, recording that you've reviewed the tax figures.
6-strategy comparison Side-by-side metrics for No Conversion, Fill 12%, Fill 22%, Optimal Mix, IRMAA-Limited, and Custom.
Confidence scoring 6 checks with pass/warn/fail ratings covering tax torpedo, IRMAA, ACA, RMD reduction, lifetime tax, and estate value.
Dual export Export scenario JSON for backup, and export `.roth-plan.json` for the companion Retirement Income Planner.
Married Filing Jointly Full MFJ support with spouse Social Security, wider brackets, and separate IRMAA thresholds.
Single self-contained file Works offline, no installation, no account, no data sent anywhere. Opens in any modern browser.
Instant digital download · No subscription · Runs locally in your browser
Disclaimer: I am not a financial advisor and none of this should be considered financial advice. This tool is for educational and personal planning purposes only. It does not constitute financial, tax, legal, or investment advice. All projections are estimates based on the values you enter and are not guaranteed.
Tax laws, ACA rules, Medicare premiums, Social Security benefit structures, and UK tax parameters change regularly. You are responsible for verifying that the figures used in your plan reflect current law. Use the Rate Research Prompt to check key parameters against an AI assistant, and always consult a qualified financial advisor, tax professional, or retirement planner before making any financial decisions.
