MOI stands for "moment of inertia" and is a measurement of how much resistance a golf clubhead has to twisting when it makes contact with the ball. It is measured in grams per centimeter squared and the higher the MOI reading, the more resistance the clubhead has and the more forgiving the club will play. A higher MOI club will have a more efficient energy transfer on mishits, causing a smaller drop in ball speed on those off-center strikes. Clubs with a higher MOI deliver a larger sweet spot and more forgiveness, meaning youll likely find the fairway more often and enjoy the game even more.

MOI is important for golf club design because most golfers do not hit the ball in the center of the clubface all the time. On off-center hits, the clubhead is forced to rotate away from the target, resulting in a loss of directional control and ball speed. A high MOI means that the club is more stable and therefore more resistant to twisting, which translates to more ball speed and a straighter shot. For the average golfer, a high MOI is beneficial as it will lead to consistently straighter and longer shots from off-center strikes.

MOI is not only found in drivers but can also be helpful on all clubs through the bag. The higher MOI your irons have, the more stable they become at impact and the better chance you have at hitting them online and the correct distance. Even when it comes to putters, high MOI mallet designs (or blade styles with heel-and-toe weighting) can help the ball roll online without losing much speed on putts hit off-center. Highly skilled players, such as PGA Tour pros, often opt for clubs with a bit less MOI, or forgiveness, because less twisting of the face actually reduces the ability to hit draws and fades on purpose.