After your first shot on a launch monitor there are suddenly ten numbers on the screen. Some say a lot about your swing, others mostly something about the ball. Here is what each number means, which ones to keep an eye on and how the numbers turn into better club decisions on the course.
The cover image above serves as the example: a 7-iron in the DeepSwing launch monitor with 123 metres of carry, 156 metres total, 159 km/h ball speed, 15.8 degrees of launch and a start direction 2.6 degrees left.
Ball speed
Ball speed is the most important single number for distance. It depends on two things: how fast the club head is and how well you strike the ball. A strike off the toe or heel costs ball speed even if the swing was just as fast.
Club head speed
Club head speed measures how fast the head is just before impact. It is your swing's potential. If you want more distance, you work either on this number or on getting more of it into the ball. That is exactly what the next number shows.
Smash factor
Smash factor is ball speed divided by club head speed. In the camera view from our article How an iPhone measures ball flight without radar, the club head travels at 145 km/h and the ball leaves at 186 km/h: 186 divided by 145 gives a smash factor of 1.28.
As guide values, a driver reaches up to about 1.50; the rules on the springiness of the club face hardly allow more. For mid irons a good strike sits around 1.3 to 1.4, for wedges lower. A smash factor that jumps around is almost always a sign of changing strike points on the face.
Launch angle
Launch angle is the vertical angle at which the ball starts. It depends on the club's loft but also on how you deliver it at impact: hands ahead of the ball lower launch, scooping raises it. With the driver, higher launch with little spin often brings more distance, especially at slower swing speeds.
Start direction
Start direction is the horizontal angle relative to your target line, that is how many degrees left or right the ball takes off. It is mainly set by where the club face points. For this number to be right, the launch monitor has to be aligned with the target line. In DeepSwing you lay a club on the ground pointing at the target and turn the tripod until the yellow line runs along it.
Spin
Backspin determines how high the ball climbs and how quickly it stops after landing. The tilt of the spin axis decides draw or fade. A note on honesty: DeepSwing does not measure spin directly; it estimates it from club, speed and launch and labels it as estimated in the app.
Carry and total distance
Carry is the distance the ball travels in the air. Total distance adds bounce and roll, which vary a lot with the ground. So: carry is what counts for club selection. The ball only clears a bunker in front of the green in the air.
Apex and landing angle
Apex is the highest point of the flight, landing angle the angle at which the ball comes down. The steeper it lands, the faster it stops. For irons that should hold the green, a landing angle of around 45 degrees or more is a good sign. Shallow landing angles roll further, which can be welcome with the driver.
The numbers at a glance
| Number | What it tells you | What you work on |
|---|---|---|
| Ball speed | how much energy reaches the ball | strike point and swing speed |
| Club speed | the swing's potential | technique, mobility, strength |
| Smash factor | quality of the strike | strike point on the face |
| Launch angle | height of the start | ball position, shaft lean |
| Start direction | direction of the start | where the face points |
| Spin | height, curve, stopping | loft at impact, swing path |
| Carry | distance in the air | the basis of club selection |
| Landing angle | how quickly the ball stops | launch and spin |
From numbers to club selection
The biggest value of a launch monitor is not the single record shot but reliable distances per club. Here's how to get there:
- Hit ten balls per club, after warming up and with your normal swing.
- Take the average, not the best shot. On the course the best shot is the exception.
- Look at the gaps. If two clubs are less than about ten metres apart, or there is a big hole, it is worth looking at your set.
- Watch the dispersion. DeepSwing shows per session how many balls finished left, straight and right. A tight dispersion is often worth more on the course than ten extra metres.
DeepSwing keeps statistics per club and exports them as a PDF. And the golf course GPS uses these distances directly: on the hole, next to the distance, you see the club that matches your launch monitor carry. How that works together with elevation is in Plays-like distance.
Frequently asked questions
Which launch monitor number matters most?
Ball speed for distance, carry for club selection. Smash factor shows fastest whether a problem is down to the strike point.
What is a good smash factor?
Up to about 1.50 with the driver, around 1.3 to 1.4 with mid irons. More important than the peak is that it stays the same from shot to shot.
Why is carry more important than total distance?
Because hazards have to be cleared in the air, and roll depends on the ground, which is different on every course and in every kind of weather.
Does DeepSwing measure spin?
No, spin is estimated from club, speed and launch and labelled that way in the app. Ball speed, launch, direction and club speed are measured.
Measure your own numbers: the DeepSwing launch monitor, five free shots a week.