Moment of Inertia (MOI) measures a club’s resistance to rotation, which directly affects its stability at impact. Balanced with other functional components of performance, MOI contributes to what golfers commonly experience as “forgiveness.” 


While players may think of MOI as a singular number, it’s really a combination of measurements across three distinct planes:

1. Heel-to-Toe
2. Crown-to-Sole
3. Club Face to Trailing Edge 

With increased stability across each of these planes, the club transfers more energy into the ball, leading to ball speed preservation and reduced sidespin on off-center strikes.

A club with higher MOI will stay more stable through impact, preserving ball speed and reducing Gear Effect on off-center hits. However, while some may equate MOI to directly forgiveness, it is only one part of the equation. Stability words in tandem with design features like Bulge & Roll and Center of Gravity (CG) location to produce the full experience of forgiveness.

It’s also worth noting that excessive MOI reduce maximum distance. Higher inertia means more resistance to twisting and turning, slowing down clubhead speed as a result.

To find the best balance of MOI, CG, Coefficient of Restitution (COR), and aerodynamics for specific player profiles, Titleist combines each of these performance features in several unique ways. By creating a range of model options, golfers can choose the best blend of performance attributes to fit their individual playing style.