Technologies for performing orientation-independent bioimpedance-based user authentication include a compute device. The compute device includes a plurality of electrodes usable to transmit an alternating current and measure a bioimpedance in a section of the body of a user. The compute device is to transmit, with a pair of the electrodes, an alternating current through the section of the body of the user, measure, with a pair of the electrodes, a bioimpedance of the section of the body to the transmitted alternating current, generate a tomographic image as a function of the measured bioimpedance, identify a position of a fiduciary marker in the tomographic image, rotate the tomographic image to a predefined orientation as a function of the position of the fiduciary marker, extract one or more biometric features from the rotated tomographic image, and perform authentication of the user as a function of the extracted one or more biometric features.
