Thanks to the Warren Buffett-backed Billion Dollar Bracket, more than ever before, outlets are reporting that the odds of picking a perfect bracket are "1 in 9.2 quintillion." This figure has been cited by *The New York Times*, *USA Today*, *Slate*, *Bleacher Report*, *CBS*, and Rick Reilly, among others, and it has to stop.

As most of these articles mention (after they've had their fun with this enormous number), 9.2 quintillion is 2^63, which means 1 in 9.2 quintillion are the odds of picking a correct bracket if you flip a coin for 64 games. Nobody actually picks brackets this way; even *very* casual fans incorporate relative seeding. For all practical purposes, 1 in 9.2 quintillion is a terrible estimate of how hard it is to pick a perfect bracket.

So what are real chances, if you're making even a somewhat informed decision? It's very difficult to calculate—Buffett himself has said that "Einstein himself could not figure out the odds"—but DePaul mathematician Jeffrey Bergen puts it at as low as 1 in 128 billion.

128 billion is still an enormous number—nobody's about to win Buffett's money—but it's not an astronomical one. If all seven billion people on Earth filled out a somewhat informed bracket with these odds, over the course of 13 years, chances would be greater than not (51 percent) that someone would nail it. If everyone filled out a coin-flip bracket, that break-even would come over the course of 911 million years.