Launch monitors have become the standard tool in modern club fitting, using Doppler radar or high-speed cameras to measure ball and club data on every single swing. Here's a plain-English guide to the numbers you'll see during a session.
Ball Speed
How fast the ball is traveling immediately after impact, measured in miles per hour. Ball speed is the single biggest driver of distance — more ball speed generally means more carry, assuming launch angle and spin are reasonably efficient.
Clubhead Speed
How fast the clubhead is moving at the moment of impact. Clubhead speed and ball speed are related but not identical — the relationship between them is captured by smash factor.
Smash Factor
Smash factor is ball speed divided by clubhead speed, and it's a direct measure of strike efficiency. A perfectly center-struck driver shot typically produces a smash factor around 1.50; a mis-hit toward the toe or heel lowers that number even if clubhead speed stays the same. Smash factor is one of the clearest signals of contact quality on the screen.
Launch Angle
The vertical angle the ball leaves the clubface, measured in degrees. Launch angle works together with spin rate to determine trajectory and hang time — too low and the ball can't carry far enough; too high and it can balloon and lose forward distance.
Spin Rate
How fast the ball is spinning immediately after impact, measured in revolutions per minute (rpm). Spin affects both trajectory shape and how the ball behaves on landing — higher spin generally means a steeper descent and more stopping power, while lower spin produces a flatter flight with more roll.
Spin Axis
The tilt of the spin axis relative to vertical, which determines whether the ball curves left or right. A spin axis tilted to the right (for a right-handed golfer) produces a slice or fade; tilted left produces a hook or draw. Spin axis is often the clearest indicator of what's happening at impact in terms of face angle relative to swing path.
Attack Angle
Whether the clubhead is moving upward or downward at the moment of impact, measured in degrees. A negative attack angle means you're hitting down on the ball (typical and desirable with irons); a positive attack angle means you're hitting up on the ball (often desirable with a driver on a tee).
Carry Distance vs. Total Distance
Carry distance is how far the ball travels in the air before landing. Total distance adds roll after landing. Launch monitors typically show both, and the gap between them tells you how much your trajectory and spin are contributing to roll versus carry.
No single number tells the whole story — a good fitter reads all of these together to understand what's really happening at impact, not just the final distance number.
Why This Matters for You
Understanding these numbers means you're not just taking a fitter's word for it — you can see for yourself why a particular loft, shaft, or head change produced a measurable improvement, and make an informed decision about your equipment.