Younger taxpayers can skip the math exercise.
For people with a long time horizon, the Roth makes the most of the phenomenon known as compounding - the multiplying of your money over time. And the well-heeled might go the Roth route for estate planning, since there are no mandatory withdrawals. Converted money must stay in the account five years. Whether you're converting a traditional IRA or just thinking about opening a new account, Web sites and worksheets are ready to help you reckon with Roth. Mutual-fund Internet sites let you plug in your tax bracket and other numbers to see if a Roth IRA is right for you.