How Many Dimples Are On A Golf Ball And Does It Matter?

A golf ball is a small white ball consisting of a rubber core. Golf balls have a hard outer shell made of surlyn or urethane that helps the ball to spin. Molded on the cover are tiny dimples with an average size of 3.5 mm and the depth of each dimple ranges from 0.5 to 1.5 mm.

Now, some golfers are fascinated and intrigued by the indented dimples on the golf ball. One popular question I get about the golf ball is how many dimples are there? I did a little research and here is what I found:

In short, most commercially manufactured golf balls have between 300 to 500 dimples molded on the outer shell. This is enough dimples to indent on a golf ball with a typical diameter of 42.67 mm. 

On the other hand, there are some golf balls that are well outside the average dimple count such as the Dimple 1070 that contains a total of 1070 dimples. However, these types of golf balls are not regulation-grade and cannot be used in competitve matches.

Not only does the amount of dimples vary on the golf ball, but also their size, shape and depth. The table below shows some of the most popular golf balls and the number of dimples they contain.

As you can see from the table above, the best golf balls in the market typically have a dimple count ranging from 300-400. In fact, most of the golf balls on the conforming list of the United States Golf Association fall somewhere in this range.

Does The Number Of Dimples On A Golf Ball Matter?

Golf balls are one of the most recognizable designs in all of sports. What makes the golf ball so unique is not just it’s small shape, but hundreds of small impressions or dimples on it’s surface.

Dimples are crucial to a golf ball’s flight. A golf ball has dimples that will reduce wind resistance or aerodynamic drag. When this is reduced, the golf ball travels farther.

Early golfers using smooth golf balls realized that the more they used a golf ball, the farther it will go as the surface gets scuffed and knocked about. As a result, they decided to mold dimples on the surface.

As the golf ball flies through the air, the airflow interacts with the surface of the ball and can greatly affect the amount of drag.

The wind meets the surface and push against the golf ball. This cause the wind to wrap around the golf ball.

If the golf ball was smooth, the air flowing closest to the surface of the ball will follow the flow of air around it, creating a detached airflow behind the ball.

As air flows around the smooth golf ball, it becomes detached. The air that is closest to the surface doesn’t want to stick to the surface but to the fast moving airflow.

The detatched flow causes a wake to form behind the ball which creates a low pressure zone. This zone is what causes drag.

It’s almost like a vaccum that is sucking the ball back and slowing it down in the face of the wind. Adding dimples to the ball changes how the air flows over it.

As the air travels over one of the dimples, a tiny pocket of turbulence or air disturbance is created on the surface.

The air tries to go in and then has a region where it’s actually detached and then by the time the air gets to the next dimple of the ball, it reattaches itself. In the process of the dettachment and reattachment, the turbulence is formed.

Instead of impeding the flight of the ball, these tiny pockets of turbulence allow the closer layer of air to travel tighter around it.

Because the dimples have caused some low level turbulence, it’s mixing the high speed air and bringing it close to the ball so that the flow can remain attached to the ball.

A more attached airflow creates a smaller wake, and thus a smaller low pressure zone which means less drag. Even a slight change can make a big difference.

A golf ball with dimples will go as twice as far as a golf ball without. The dimples also aid the flight of the ball by influencing the lift as the ball spins through the air. Lift force is a result of a concept of aerodynamics known as ‘Bernouli’s Principles’.

The Principle states that as the speed of the airflow increase, the pressure of the airflow on the ball is decreased, thus creating lift.

The lift is pronounced due to the dimples on the ball. Though tested for their effect, the United States Golf Association does not regulate golf ball dimples. Therefore, you can have any number and any shape golf dimples.

The effect of golf dimples are tested and measured at the USGA’s 70 foot indoor test range in New Jersey.

Golf balls are launched through a series of censors at upwards of 190 miles per hour. These info red censors can precisely track the trajectory of the golf ball so that computers can figure out how much areodynamic lift and drag force each type of dimple pattern produce.

While dimple sizes, shape and effects may differ, they remain a crucial aspect in all golf ball designs.

Related post: Does used golf balls lose distance

Final Verdict

A golf ball will be useless without dimples. It simply wouldn’t get anywhere and it would be almost impossible to keep in play. On the other hand, we shouldn’t mistake more dimples for more distance as too much dimples can increase the drag over the golf ball surface resulting in a lower trajectory. As a rule of thumb, golf balls should have between 300-500 dimples.

You can expect to get a maximum of 130 yards from a golf ball without dimples using a typical driver to the hit the ball carried out by a skilled male golfer.

All in all, dimples are necessary for the distance the golf ball travels, but most importantly are the shape and depth of the dimples that will create the turbulent of air needed that will cling to the ball’s surface. This thin turbulent boundary layer of air will allow smoothly flowing air to follow the ball’s surface a little farther around the back side of the golf ball which reduces the size of the wake. That is how the golf ball actually gains distance.