Method and contact lens (3) for measuring a subject's eye movement. A video camera (1) is provided for recording an image of the subject's eye (2). The contact lens (3) is provided for placement over the subject's eye (2). The contact lens (3) comprises one or more markers (3a,3b) that are detectable by the video camera (1) and are positioned at a lateral offset (D) with respect to a central part (3p) of the contact lens (3). The one or more markers (3a,3b) are configured for detecting torsional rotation (R) of the subject's eye (2) around a line of sight axis (C) of the subject's eye (2) by using the video camera (1) to track a position of the one or more markers (3a,3b).
