An input device includes: a sensor; a detection circuit which, in operation, detects a first indicated position indicated by an electronic pen in a two-dimensional space in accordance with transfer of a signal between the electronic pen and the sensor; one or more processors; and one or more memory devices storing instructions that, when executed by the one or more processors, cause the one or more processors to: detect a second indicated position indicated by the electronic pen in a three-dimensional space, and generate position information of the electronic pen in the two-dimensional space or the three-dimensional space based on the second indicated position and first indicated position. The input device enables a position indicated by the electronic pen and a pen posture of the electronic pen in the three-dimensional space to be detected in a satisfactory manner in view of precision and response speed.