A Swiss ball is a ball constructed of elastic soft PVC with a diameter of around 35 to 85 cm (14 to 34 inches). It is used in physical therapy and exercise.

The Swiss ball is also known by a number of different names, including balance ball , birth ball , body ball , exercise ball , fitness ball , gym ball , physioball , pilates ball , sports ball , stability ball , swedish ball , therapy ball , or yoga ball . It is larger and much lighter than a medicine ball.