What Are the Odds of a Hole-In-One?

By: John Donovan  | 
Justin Thomas Masters
Justin Thomas plays his shot from the 14th tee during the second round of the Masters on April 12, 2019 in Augusta. He later shot a hole-in-one on the 16th hole during the final round on Sunday. Kevin C. Cox/Getty Images

A standard, regulation-sized golf ball is a smidge smaller than 1.7 inches (4.3 centimeters) in diameter. Or, for comparison's sake, just a little larger than your garden-variety ping pong ball.

The standard, round cup that snuggles into an earthen hole on your run-of-the-mill manicured green on any of the more than 15,000 golf courses in the United States — or the more than 33,000 throughout the world — is, by rule, 4.25 inches (10.8 centimeters) in diameter.


Small ball. Big hole. So, what's the problem? Said no one who ever swung a club at a golf ball in his or her life.

Golf is hard. Getting that little ball into that not-so-big cup is way more difficult than Tiger Woods and those other professionals make it look. And for proof (other than trying it yourself, that is), the non-golfer should consider the Holy Grail of golf, the ever-elusive, never-foreseen, always-magical hole-in-one.

If golf is hard — and, again, give it a try if you've never — the quest for a hole-in-one is downright cruel. The odds of it are not hitting-the-lottery odds. But they might as well be.

To be sure, pros like Bryson DeChambeau and Justin Thomas can pop in an ace every once in a while. (And on the same day at the most prestigious tournament in the world, The Masters, no less.) But for your average golfer? Let's go to the scorecard:

According to the National Hole-In-One Registry, which a tad immodestly back-slaps itself as "The Premiere Worldwide Hole-In-One Golf Registry," somewhere north of 128,000 holes-in-one are registered every year. Which sounds like a lot. Except golfers play somewhere around 450 million rounds of golf every year.

That means a hole-in-one is officially registered about once every 3,500 rounds. (A round is generally considered 18 holes, though the United States Golf Association sometimes accepts a hole-in-one on a shortened round.) If you play a round of golf a day, it'd take more than 9.5 years to get in 3,500 rounds. If you play twice a week, it'd take you more than 33.6 years to get in 3,500 rounds.

Another business, National Hole-In-One Insurance — it provides protection to golf courses that give out prizes for holes-in-ones during competitions — estimates that, for your average player, the odds of holing out in one stroke are 12,000 to 1. A PGA Tour pro, like DeChambeau or Thomas, faces 2,500-to-1 odds. On every chance at an ace.

The numbers, undoubtedly, are a little sketchy. The USGA isn't exactly looking over every golfer's shoulder. Video proof is not required. A credible witness is about all you need.

Still, as any weekend duffer who's gone at the pin on a par 3 knows, just about any ace (flat-out cheating and do-overs notwithstanding) is a legit ace.