Abstract According to the increasing knowledge of the risks and hazards of exposure to radiation connected with repeated radiographic investigations of spinal curvature and spinal movements, efforts are continuously being made to develop skin-surface devices for use in diagnosis and monitoring the progression and response to treatment of various spinal disorders. Nevertheless, the reliability and validity of measurements registered with such devices must be certain before they can be introduced for use in the research or clinical environment. The aim of this study was to estimate the reliability and accuracy of measurements using a newly expanded skin-surface device, the Spinal Mouse®. We accomplished our study with 62 healthy volunteers (age 21.3±1.8 years) who took part in our investigation. Spinal curvature was measured with the Spinal Mouse® in standing, full flexion, and full extension positions. Paired t-test, intra-class correlation coefficients (ICC), and standard errors of mean (SEM) with 95% confidence intervals were used to characterize the interexaminer reliability of the thoracic and lumbar curvatures, inclination, sacral angle, and length of the back in upright, flexion, and extension positions. To investigate interexaminer reliability two examiners carried out their own assessments. Our results indicate that the reliability of the spinal mouse is relatively high, good, or at least fair in different spine positions and at different segments, which can be improved further by training of the examiners. Based on our study the accuracy of the spinal mouse is not good in every case, but it is supposed that with practice it can be improved. The highest uncertainty can be seen during measuring the thoracic curvature and inclination in upright position, but the examiners produced systematic deviations. The linear correlation coefficients were the best and the p values highest in flexion position of the trunk. The results are in good agreement with data from literature regarding reliability and accuracy of the measurements.