The mind-boggling odds of a perfect March Madness bracket
At odds of 120.2 billion to one, you're more likely to be struck by lightning, win the lottery or have quintuplets than to pick a perfect NCAA Tournament bracket.
Year after year, millions of people fill out their NCAA Tournament bracket. Year after year, every single one of those brackets is busted.
Whether you’re a college basketball fanatic who puts months into researching potential champions, upsets and Cinderella stories, or a casual fan who picks winners almost at random, the likelihood is that you’ve never come close to a perfect March Madness bracket.
Like sports betting, for many attempting to nail the bracket has become a become a huge part of enjoying the NCAA Tournament.
A look at the unthinkable odds of correctly predicting all 63 games of the tournament shows why – as far as we know – nobody has ever pulled it off, and why it’s almost certain that nobody ever will.
The chances of correctly picking all 63 games at random are a ridiculous one in 9,223,372,036,854,775,808. That’s 9.2 quintillion.
To put the size of that number into context, 9.2 quintillion seconds is the equivalent of 292 billion years.
Nobody fills out their bracket entirely randomly, though, and the odds of going 63 for 63 are, unsurprisingly, much better if you have some college basketball knowledge.
In 2020, the NCAA used data from its Bracket Challenge Game to estimate that the average player has a one in 120.2 billion chance of picking a perfect bracket.
Compared to one in 9.2 quintillion, that seems relatively realistic, but in truth it’s still an astronomical number.
Perhaps the best way to contextualise a one in 120.2 billion chance is to compare it to other extremely unlikely occurrences that are, in fact, much more likely to happen than a perfect bracket.
Take, for example, becoming a professional basketball player.
In a typical season, there are approximately 540,000 players participating in men’s high school basketball in the United States. Less than one in 35 of those goes on to play in college, and less than one in 75 NCAA senior players is drafted to the NBA.
All in all, the chances of a high school basketball player reaching the NBA are about one in 3,300. Pretty unlikely, right?
Well, that’s still around 36 million times more likely than a perfect bracket.
Next, take the probability of being dealt a royal flush – the rarest hand in a game of five-card poker – which is exactly one in 854,318. That’s 185,000 times more likely than a perfect bracket.
The odds of being struck by lightning are one in a million, 120,000 times more likely than a perfect bracket.
Being hit by a meteorite from space seems almost laughably improbable, but, at odds of around 1.6 million to one, it’s 75,000 more likely to happen to you than you are to go perfect through March.
The probability of winning the Lotto Max jackpot is 1 in 33.3 million – 3,610 times more likely than the perfect bracket – while quintuplets occur once in every 55 million natural births, making them 2,185 times more likely than going 63 for 63 this March.
Nevertheless, the hunt for the perfect bracket continues, and this year many of those searching for college basketball’s holy grail will be spurred on by the efforts of Gregg Nigl, who at the last NCAA Tournament in 2019 came closer to a perfect bracket than anyone before him.
Nigl went 49 for 49 to start the tournament, correctly predicting the result of every game all the way into the Sweet Sixteen before Purdue beat Tennessee to end his streak.
Nigl’s run was incredibly impressive, considering the odds of picking just the first round of games correctly are around 17,000 to one.
Nevertheless, the perfect bracket was still a long way off. The chances of him nailing the final 15 games from the Sweet Sixteen onwards were still around one in 32,786.
And so we must accept that we’ll probably never see a perfect NCAA Tournament bracket. This March, millions will pore over the stats and seedings, only to see their bracket busted unceremoniously on day one.
It only takes one, though. Who knows? This might be your year.