An activity tracking racquet attachment device tracks activity such as calories burned over a period of using a racquet to which the device is attached. The device includes a housing having a first face and a perimeter sidewall extending from and around the first face. A processor is coupled to the housing. A motion detector is coupled to the housing such that the motion detector detects movement of the housing. The motion detector is communicatively coupled to the processor wherein the processor receives motion data from the motion detector. A coupler is coupled to and extends from a second face of the housing coupling the housing to an end of a handle of a racquet such that the first face of the housing faces outwardly from the end of the handle.