Retirement Planning Calculator

The planning engine solves for one of three objectives: maximum sustainable spending in retirement, earliest possible retirement age, or largest inheritance. It holds the other two fixed and searches for the best answer.

Savings waterfall determines the optimal order to fund your accounts each year — employer match first, then HSA, then the mix of traditional and Roth that minimizes lifetime taxes. The order depends on your current marginal rate, expected retirement rate, and account-specific rules (contribution limits, catch-up provisions, mega backdoor Roth eligibility).

Social Security: the engine tries every pair of claiming ages from 62 to 70 for you and your spouse, runs your whole plan for each pair, taxes included, and keeps the pair that does best at the ages you expect to live to. Waiting often wins, because each year you wait past full retirement age raises the benefit by 8% for life, but a shorter life, other income or your tax bracket can change the answer. A benefit you already collect is treated as a fact, not decided again.

Roth conversions: in every year of the plan, the engine tries converting up to each point where the tax rules change: the top of a tax bracket, a Medicare premium surcharge tier, the income limit for ACA subsidies, the point where more of your Social Security becomes taxable. It keeps the amounts that do best for your goal. Conversions usually land in the low-income years between retiring and required withdrawals, but they can also come while one of you still works or after required withdrawals begin, and paying a surcharge now is sometimes worth the tax it saves later.

Withdrawals: there is no fixed order such as “taxable first, then traditional, then Roth.” Each year the engine tries different orders for drawing on your taxable, traditional, Roth and HSA accounts, runs the whole plan for each one, and keeps the order that does best. Along the way it can sell taxable investments up to the amount taxed at 0%, spend Roth contributions before 59½ (they come out free of tax and penalty), and it always takes required minimum distributions when they are due.