The Roth Conversion Optimizer is a tab on the Optimizers page. It tests several common Roth conversion strategies against your full plan using the same Monte Carlo simulation as the dashboard, then ranks them by net (after-tax) ending wealth, with success rate as a secondary check.

The strategies it tests include:

• No conversions - the comparison baseline.
• Fill X% bracket - convert each year up to the top of the 12%, 22%, 24%, 32%, or 35% federal bracket (capped by your "Maximum target bracket" setting).
• Pre-RMD bracket fill - concentrates conversions in the years before RMDs begin to flatten the RMD-era ordinary-income stack.
• ACA-aware - skips conversions in years where ACA Marketplace coverage is active, then fills brackets normally outside that window. Only shown when ACA is modeled.
• IRMAA-aware - caps conversions before they would trip the Tier 1 IRMAA threshold so Medicare premiums stay flat. Only shown when Medicare is modeled.

The optimizer never modifies your saved plan. It runs each strategy in an isolated copy and reports per-strategy lifetime taxes, average RMD, ending balance, net (after-tax) balance, success rate, and total converted, plus the top-ranked strategy's annual conversion schedule. The Roth Strategy page remains the place to fine-tune the result manually.

How strategies are ranked. The optimizer ranks on net (after-tax) ending wealth - the median end-of-plan portfolio with the remaining Tax-deferred balance discounted for the income tax still owed on it. A dollar in a Roth or taxable account is already yours to spend; a dollar in a Traditional IRA or 401(k) still owes ordinary income tax when it comes out. Counting the two equally (as a gross balance does) overstates strategies that leave more sitting in Tax-deferred, so ranking on the after-tax figure compares strategies like-for-like.

• Net (after-tax) balance is the primary metric: Taxable + Roth + Cash + Tax-deferred x (1 - an assumed liquidation tax rate). For a strategy that ends with nothing left in Tax-deferred, the net and gross balances are identical.
• Success rate is the secondary signal - the share of Monte Carlo paths where the plan did not run out of money - because a wealthier plan that is also riskier is not automatically the better choice.

Lifetime taxes and RMDs are shown but not ranked on. Both are already reflected in after-tax wealth - paying conversion tax, or taking an RMD and paying tax on it, lowers your net balance - so scoring them separately would double-count the same effect and can wrongly reward "pay the least tax" over "keep the most money". They stay in the table as useful detail, not as goals in themselves.

A single top pick can hide a real trade-off: the wealthiest strategy is sometimes slightly less safe, or the safest slightly less wealthy. It is worth scanning the whole table - the Net (after-tax) and Success columns matter most - since the best choice for you may weigh safety differently than the default ranking does.

When two strategies produce the same conversion schedule for a given plan (common when the user has already started Social Security and all conversion years are pre-RMD), the optimizer combines them into one row to keep the comparison table focused.