CT (Characteristic Time)

Characteristic Time, or CT, measures how long the clubface stays in contact with the ball at impact. It’s used to gauge face flexibility, especially in drivers and fairway woods. A higher CT means the face is flexing more and transferring energy more efficiently, which can help produce higher ball speed. The USGA sets a strict limit to ensure no club provides an unfair distance advantage.

Club manufacturers and fitters check CT to make sure a clubhead sits within legal limits and performs consistently. Two heads of the same model can vary slightly, so CT testing helps identify heads that are on the higher end of allowable performance.

For golfers, it’s mainly a behind-the-scenes quality control measure, but it plays an important role in how reliably and efficiently a club generates speed.