To accurately provide a state of busyness in a store to customers without burden on a clerk.

A degree of busyness calculation device includes: an order information acquisition unit 110 for acquiring order information that shows order contents; an order information management unit 140 for storing and managing the acquired order information in a management memory 22; a degree of busyness calculation unit 160 for calculating a degree of busyness in a store on the basis of at least one of the number of the order information stored in the management memory 22 and the number of orders for respective items that are included in the order information stored in the management memory 22; and a degree of busyness output unit 180 for outputting the calculated degree of busyness to an external device.