Clubhead Speed
Also called: swing speed
How fast the clubhead is moving at impact, measured in mph - the primary driver of distance and a key input for shaft and flex selection.
Clubhead speed is how fast the head of the club is traveling at the moment of impact, measured in miles per hour. It is the engine of distance: all else equal, more speed means more ball speed and more carry. It is also the single most important number for choosing the right shaft and flex.
Driver speed is the figure most often quoted. A typical male recreational golfer swings the driver somewhere around 90 mph; tour players are commonly 110-120+. But speed varies through the bag - your wedge speed is far lower than your driver speed - which is part of why a single flex does not always carry across every club.
Speed drives flex selection, but not by itself. Two golfers at the same speed can need different shafts because tempo and the timing of force delivery differ. A smooth 100 mph swing loads a shaft differently than an aggressive, late-release 100 mph swing. Speed sets the rough range; how you generate it fine-tunes the choice.
Chasing speed is popular, but for most golfers center contact and consistency produce more usable distance than raw mph. Speed only helps when you find the middle of the face.