 This study proposes two algorithms to determine the midpoint on the leg or foot outline. The midline has been computed by linear regression through five midpoints. The leg and foot angles are calculated by the tibial and calcaneal midlines, respectively. By selecting the midpoint algorithm of the limit points and the lowest point methods to determine the tibial and calcaneal midlines, the results will be more accurate. The foot 3D scanning measurement proposed in this study has been tested and validated from the goniometer. It provides guidance for foot posture assessment and personal insoles designed in the future. This article was authored by Qianheng Lin and Yin Yu Lin.