An absolute rotary encoder (1a, 1b, 1c) comprising: a scale (10, 110, 210) on which a first track and a second track are provided with different diameters from each other; a first sensor (20, 120, 220) configured to move relative to the scale and read the first track and the second track; a second sensor (30, 130, 230) arranged so as to face the first sensor in a radial direction of the scale and configured to move relative to the scale and read the first track and the second track; and a processor (500a, 500b, 500c) configured to generate a first absolute position signal by taking a difference between a first periodic signal based on a signal obtained by reading the first track by the first sensor and a second periodic signal based on a signal obtained by reading the second track by the first sensor, and to generate a second absolute position signal by taking a difference between a third periodic signal based on a signal obtained by reading the first track by the second sensor and a fourth periodic signal based on a signal obtained by reading the second track by the second sensor, characterized in that the processor is configured to average the first absolute position signal and the second absolute position signal to generate a third absolute position signal, to combine the thirc absolute position signal and the first periodic signal to generate a fourth absolute position signal, to combine the third absolute position signal and the third periodic signal to generate a fifth absolute position signal, and to average the fourth absolute position signal and the fifth absolute position signal to generate an absolute position signal indicating an absolute position of at least one of the scale, the first sensor, or the second sensor. a scale (10, 110, 210) on which a first track and a second track are provided with different diameters from each other; a first sensor (20, 120, 220) configured to move relative to the scale and read the first track and the second track; a second sensor (30, 130, 230) arranged so as to face the first sensor in a radial direction of the scale and configured to move relative to the scale and read the first track and the second track; and a processor (500a, 500b, 500c) configured to generate a first absolute position signal by taking a difference between a first periodic signal based on a signal obtained by reading the first track by the first sensor and a second periodic signal based on a signal obtained by reading the second track by the first sensor, and to generate a second absolute position signal by taking a difference between a third periodic signal based on a signal obtained by reading the first track by the second sensor and a fourth periodic signal based on a signal obtained by reading the second track by the second sensor, characterized in that the processor is configured to average the first absolute position signal and the second absolute position signal to generate a third absolute position signal, to combine the thirc absolute position signal and the first periodic signal to generate a fourth absolute position signal, to combine the third absolute position signal and the third periodic signal to generate a fifth absolute position signal, and to average the fourth absolute position signal and the fifth absolute position signal to generate an absolute position signal indicating an absolute position of at least one of the scale, the first sensor, or the second sensor.