[Problem] To provide a drowsiness calculating device capable of calculating drowsiness with a high degree of accuracy. [Solution] In a drowsiness estimating device 1, a drowsiness reference heart rate calculating unit 4 calculates a cumulative average heart rate by dividing a cumulative total number of heartbeats acquired by means of an interface 7, from when a state of activity of a user changes, by time. A drowsiness reference heart rate which serves as a reference for determining whether the user is experiencing drowsiness is calculated on the basis of the cumulative average heart rate. Furthermore, a drowsiness calculating unit 5 estimates the current drowsiness of the user on the basis of the drowsiness reference heart rate and the current heart rate.
DROWSINESS ESTIMATING DEVICE