What it measures
Club speed is how fast the clubhead is moving in the last moment before it touches the ball, measured near the middle of the clubface. It is measured in miles per hour (or kilometers per hour or meters per second). It is a speed only, with no direction, so it is always a positive number and reads the same for right and left handed golfers. Because it is taken just before the collision, a mishit does not lower club speed the way it lowers ball speed.
It describes the club, not the ball. Two swings with the same club speed can produce very different results depending on where the ball is struck and how the face and path are delivered.
Typical numbers
PGA Tour players average about 115 mph of driver club speed, with a 7 iron around 90 to 92 mph and a pitching wedge in the low 80s. LPGA Tour players average roughly 94 to 96 mph with driver and the mid to high 70s with a 7 iron. Exact figures shift a little from year to year.
Everyday golfers vary widely. The average male amateur swings driver around 93 mph, and many recreational players fall between about 80 and 100 mph. Women amateurs commonly swing driver somewhere in the 60s to 80s. Speed drops as clubs get shorter and more lofted, so always compare a club against itself.
What changes it
Speed comes from how efficiently the body creates and passes energy to the club: ground pressure, rotation, arm speed and release timing. Longer and lighter clubs are generally faster for the same effort, which is why driver is the fastest club in the bag. Shaft length, total weight and swing weight all play a part.
Fatigue, tension and a cold body usually lower it. Trying to swing hard often raises speed a little but can cost strike quality, which matters more for the final result.
What it changes
Club speed is the main source of ball speed. Ball speed equals club speed times smash factor, so more club speed with the same contact means more ball speed and more distance. A common rule of thumb is that each extra mph of driver club speed is worth roughly 2 to 3 yards of carry, as long as launch and spin stay sensible.
It also nudges spin: for a given spin loft, faster swings produce more spin, so speed gains sometimes need a small loft or attack angle adjustment to stay efficient.
How to use it
Treat club speed as a trend, not a single swing. Hit five to ten shots and look at the average and the spread. If speed rises but smash factor and impact location fall apart, the extra effort is not helping.
A simple bay drill is speed ladders: hit three shots at a smooth 80 percent effort, three at 90 percent and three at full effort, noting club speed and smash factor for each. Many golfers find their best ball speed comes slightly below full effort. For speed training, alternate a few max effort swings with normal swings and watch whether the normal ones creep up over several sessions.