When people say that golf is a game of control, they really mean that golf is a game of spin rate.
There are other data points that get much of the attention — carry yardage, ball speed and launch angle are three of the most highlighted, and we went over them in a broader analytics post you can find here — but an argument can be made that spin is the most underrated of all the variables in golf ball launch analytics.
What Causes Spin?
Every golf ball has somewhere in the neighborhood of 300-500 dimples with most balls being in the high 300’s. The dimples are there to help lift the ball by forcing airflow downwards so the ball can be pushed upwards. This is a process that sends the ball spinning backwards after impact at thousands of revolutions per minute.
The amount of spin in this process, which is called spin rate, is a major influencer of height and distance in a golf shot. With all other variables being equal, there are two primary factors that increase spin rate:
- More loft. A 7-iron would have more spin than a 5-iron, for example. A good analogy here is a tennis racket. If you wanted to hit a high-arcing shot where the tennis ball hits the court and stops, you would open the racket more towards the sky instead of pointing it perpendicular to the ground. The same principle is true in golf. The more the clubface is pointed up to you, the more spin you are likely going to apply. This is assuming all other factors in your swing stay the same.
- More clubhead speed. A stronger, faster player hitting a 9-iron will generally produce more spin than someone who hits the same 9-iron but swings slower. If you flipped a coin without much force, it may only go end-over-end a few times. With more energy, it can go end-over-end dozens of times.
While more loft and clubhead speed create more spin, that’s not always a desired outcome because more spin makes a golf ball go shorter and stop faster. Adding spin could be useful in some situations and harmful in others.
Understanding Spin Rate Numbers
So knowing this information, the obvious question to the spin rate equation is this: when you have just hit a golf shot and go to look at each data point, what does the spin rate number actually mean?
Let’s start with a simple example. When the average PGA Tour player hits a driver, their spin rate is typically in the area of 2,700 RPMs. For a player who is a scratch handicap, their average is right around 2,900 RPMs. If you are a 10-handicap, you are probably around 3,200 RPMs.
Of course the better players are swinging faster, but they are typically using less loft and stiffer shafts to produce a lower launch. They also have a shallower angle of attack into the ball and make contact higher on the clubface. All of that combines to make for less spin and longer carry distances.
(Pro Tip: If you spray your driver with something that will create a film, like Dr. Shoal’s odor spray, you can see exactly where the ball is hitting the face. Anything low on the face will usually create a lot more spin because the ball rolls up the face during impact.)
During quarantine Bryson DeChambeau posted an Instagram video where he hit a ball 203 mph with a driver that had less than 6 degrees of loft, but the ridiculous speed caused the spin rate to go all the way up to 2,976 RPMs, which meant the ball went nowhere near its potential yardage. It was during this time that he was testing new drivers and trying to see if he could hit the ball that hard while still maintaining a low spin rate.
“If spin rate was 2,000 (RPM’s), it would fly around 360 yards,” DeChambeau said in the caption.
Rory McIlroy was recently tested on a launch monitor and his spin rate came back at 2,297 RPMs. Being able to keep the spin that low while maintaining the other metrics is something players of his caliber are constantly checking.
The lesson here? If you want the ball to go far, your spin has to get lower while your launch angle either stays the same or gets higher. A simple rule of thumb is that you want the highest launch possible with the lowest spin possible, trying to marry the two to keep them both happy. This is a bit of an oversimplification when you get deeper into the analytics game, but it’s a solid starting point.
If you have a fast swing speed and your driver spin rate is something like 3,300 RPMs, it’s possible you are playing a driver with too much loft or you are using a shaft with too much flex. It can also mean a swing adjustment is necessary. One of the biggest adjustments is shallowing out your angle of attack into the ball and making contact higher on the clubface. This is where a PGA professional or trained club-fitter could be a valuable resource.
Of course it’s possible to not have enough spin with a driver — a slower swing speed player hitting an extra-stiff shafted driver with 8 degrees of loft won’t have success because the ball would barely get airborne — but the average amateur golfer is guilty of too much spin off the tee.
A recent study showed that the average golfer has a 3,275 RPMs driver spin rate with a 12.6 degree launch angle, when the optimal “robot in the lab” relationship is 2,300 RPMs of spin with a 14.7 degree launch angle. The difference is 30 yards lost off the tee. It goes to show you that most amateurs are launching the ball too low with too much spin. Getting to 2,300 RPMs of spin is a very low number and not possible for most. However, it’s reasonable to think most golfers could realistically take a few hundred RPMs off of their drives.
It should be noted that abnormally higher spin rates with longer clubs also come with uncontrollable ball flights. For someone who hits a massive slice, it’s not uncommon to see their spin rate over 6,000 RPMs. This is a glaring sign of loss of distance and direction off the tee.
This is key information when testing a driver as well. If you hit a ball with two different drivers and they both have the same launch angle but one has more spin, the one with less spin will typically go farther. It’s hard to overestimate the impact of equipment in this equation. A great swing with an ill-fitting club is not going to work very often.
Spin Rate for Other Clubs
Moving down throughout the bag, here are PGA Tour spin rate averages for other clubs:
- 3-wood: 3,655 RPMs
- 5-wood: 4,350 RPMs
- Hybrid: 4,437 RPMs
- 3-iron: 4,630 RPMs
- 4-iron: 4,836 RPMs
- 5-iron: 5,361 RPMs
- 6-iron: 6,231 RPMs
- 7-iron: 7,097 RPMs
- 8-iron: 7,998 RPMs
- 9-iron: 8,647 RPMs
- Pitching Wedge: 9,304 RPMs
While these are professional averages, a normal player doesn’t generate the same speed. That means they would be likely aiming at spin rate ranges that are lower than a pro’s.
Unlike with the driver where amateurs have more spin than professionals, amateurs generate less spin with their irons than professionals. This is mainly because irons require more of a downward strike. For pros, a driver angle of attack is -1.3 degrees while a pitching wedge would be closer to -5 degrees. So the faster swing speed and increased loft combine with a more downward blow to create more spin.
Of course, a pro wants their irons to stop as quickly as possible. That being the case, there is much less of an incentive to reduce spin.
An Example of Iron Spin Rate
A pro swings their 6-iron around 92mph to get to 6,231 RPMs. Here are some ranges to keep in mind for more normal swing speeds:
- Swing speed between 84-91mph: 5,300-5,750 RPMs, launch angle of 15-17 degrees
- Between 75-83mph: 5,000-5,500 RPMs, launch angle of 15-18 degrees
- Between 65-75mph: 4,700-5,250 RPMs, launch angle of 16-19 degrees
- Less than 65mph: 4,400-5,000 RPMs, launch angle of 16-19 degrees
This is just for a 6-iron, but looking at the PGA Tour averages and seeing what your swing speed is with each club, you will notice the typical amateur range is normally 300-1,200 RPMs or so below that, particularly for the highest lofted clubs. The more speed you are producing, the closer to the top of the range you would expect to be.
One of the most important things to keep in mind when you are looking at spin rate is that outliers are cause for concern. If you see an 8-iron come off at 4,000 RPMs, that would be cause to look deeper at your equipment or technique. There isn’t one set spin rate to reach for every club. However, getting within a reasonable range given your swing speed and marrying it with the proper launch angle is vital.
We will have a more in-depth look at spin rates in the future. Hopefully this intro is a good foundation for understanding one of the most important metrics in golf ball launch analytics.