A sleep monitoring device (120) for monitoring sleep states of a human, the sleep monitoring device is configured to receive movement data of the resting human from a movement measurement device (112), the sleep monitoring device (120) comprises a movement data analyzer (130) configured to compute from the movement data at least: heart beat data and respiration data,and physical activity a data classifier (140) configure to determine a heart rate regularity valuation of the heart beat data within a time interval, and to determine a respiration regularity valuation of the respiration data within the time interval, a sleep classifier (150) configured to obtain a sleep state for the time interval from at least the respiration regularity valuation and the heart rate regularity valuation.
