Here’s exactly what Gates, Bloomberg and Cooperman would pay under Warren’s wealth tax

Sen. Elizabeth Warren has set her sights on taxing the ultra-rich if she’s elected president, but she’s made at least one thing easier for some of them: A one-click shortcut to see just how much they’d pay.

The Democratic presidential candidate on Thursday posted a “Calculator for the Billionaires” on her campaign website. “Some billionaires seem confused about how much they would pay under Elizabeth’s Ultra-Millionaire Tax,” it reads. “Don’t worry, now we have a calculator for that too.”

“Are you a billionaire?” it asks.

If you click “Yes,” it...