According to one embodiment, a respiratory measurement module measures a first signal related to a respiratory fluctuation of the user. A body movement measurement module measures a second signal related to a movement of a trunk of the user. A respiration detector detects whether or not the user is in a respiratory arrest state, based on the measured first signal measured. A body movement detector detects whether or not the trunk of the user is moving, based on the measured second signal. An estimation module estimates a respiratory state of the user, based on a detection result by the respiration detector and a detection result by the body movement detector. An output module outputs respiratory state information indicating the estimated respiratory state.
