Dimples: all golf balls have them, but do you know why? Those little round depressions on the outside cover of your golf ball serve an important purpose, and golf brands spend millions of dollars a year in search of the perfect number and orientation.

So why do golf balls have dimples?

The purpose of dimples on a golf ball

As you might suspect, dimples on a golf ball affect its ability to fly after being struck by a golf club.

According to Scientific American, a golf ball with no dimples – or a complete smooth outer layer – would travel only about half as far as a golf ball with dimples. While the moment of impact on a golf ball lasts only a few milliseconds, it can impart the golf ball’s velocity, launch angle, and spin rate. From there, gravity and aerodynamics take over to “control” how far your golf ball will travel.

The concepts of lift and drag are the primary movers of a struck golf ball, which result in how high and far your ball will travel. Drag acts to directly oppose motion, acting as a force against any object in the air. Lift, however, acts in a direction perpendicular to motion and boosts the object upwards.

Once struck, a golf ball’s dimple pattern goes to work. Backspin is almost immediately imparted on the ball due to the loft of the golf club and good old-fashioned physics. If a golf ball was completely smooth with no dimples, this backspin would warp the air around it and produce an unpredictable amount of lift. When dimples are added to the ball’s design, however, the air has somewhere to go around the ball. This allows more lift to occur as the force of lift is optimized in relation to the quality of strike from the club.

This combination of drag, lift and velocity equates to the total carry distance of a golf ball. When you see or hear marketing taglines of modern golf ball brands, more often that not they will promise “improved distance” or a similar variant. Since golfers prefer to hit the ball farther than shorter, golf companies everywhere continuously search for the perfect formula to provide the maximum possible distance from their products.

Dimples also play a role in the shape of a golf ball’s trajectory. Accuracy is an imperative part of golf, and dimples allow for a repeatable shot shape if struck in a pure, consistent manner. A golf ball’s dimple construction will allow the ball to cut through the air with back and sidespin, create a ball flight shape. A ball without dimples, however, would fly in an unpredictable manner that will be more difficult to repeat.

Finally, dimples play a minor role in the amount of spin a ball will have when landing on the turf. While the concepts of drag and lift require backspin to produce optimal results, the dimpled depressions on a golf ball’s outer layer also feature a “gripping” quality when interacting with the fairway or green. While the actual material of the outer layer plays a larger role in this phenomenon, the backspin created as a result of the ball’s dimple pattern is an important variable in the equation.