Bearing balls are special highly spherical and smooth balls, most commonly used in ball bearings, but also used as components in things like freewheel mechanisms. The balls come in many different grades, as defined by the American Bearing Manufacturers Association (ABMA), which defines the precision of the balls. They are manufactured in machines designed specially for the job.

A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races.