What converting to a Roth costs you this year

You choose the amount. This works out what it costs — the federal tax, the Social Security it drags into income, the Medicare surcharge that lands two years later, and how much smaller your required withdrawals become.

A conversion cannot be undone.

Recharacterizing (reversing) a conversion was repealed for tax years after 2017. Once the money moves and the year closes, the tax is owed. This page tells you the consequences of an amount you pick; it does not pick an amount, and it cannot see the rest of your return.

The account

Amount you're thinking of converting Try a few figures. The cost is not proportional — thresholds sit in the way.

Traditional IRA / 401(k) balance Before the conversion. Used to work out how required withdrawals change.

Date of birth Sets the age your required withdrawals begin — 73 or 75, by birth year.

This year's income

Filing status

Other ordinary income Pension, withdrawals, wages, taxable interest — everything but Social Security and this conversion.

Social Security for the year The full amount. Enter 0 if you haven't started.

Tax-exempt interest Municipal bond interest. It is added back for both calculations below.

How many of you are 65 or older

Your state's marginal rate on this You enter this — state rules on retirement income are too varied to guess.

Where these figures come from

Also on this site: the required withdrawal (RMD) calculator, the Social Security calculator, the married-couple figures, and your retirement timeline. Multi-year conversion ladders and the lifetime tax comparison are in the iPhone app.

Estimates and general information only — not tax, investment, or financial advice, and not a substitute for your own tax professional. Not affiliated with the IRS, the Social Security Administration, or any government agency. Nothing you type here leaves your browser. Tax rules change; check figures against current official materials before acting on them.