To quantify the range, velocity, and smoothness of wrist circumduction, to explore the oblique functional plane of wrist circumduction, and to establish the reproducibility and reliability of these measures. Forty healthy subjects with a mean age of 43 years and without a history of wrist pathology or pain participated in this study. We used a flexible electrogoniometer with a twin-axis sensor to measure the relative angles between the 2 end blocks while the subject performed maximum excursion of flexion-extension, radioulnar deviation, and circumduction of the wrist held in a standardized, fully pronated position. A software package was used to further analyze the characteristics of the circumduction curve or oval such as the mean area (designated as degree-degree or oo) shape, size, rate, smoothness, and orientation. The mean area of circumduction (4729 [degree-degree]) and circumference (265°) of the circumduction curve indicated the total range of circumduction. The velocity of circumduction (mean 179°/s) and the time (1.6 second) taken to complete 1 cycle of circumduction were similar in both hands. The 4 quadrants for the velocity of circumduction showed that the velocity was faster in the radioulnar deviation quadrants compared with flexion and extension. Quadrant analysis showed the smoothness was greater in the radioulnar deviation quadrants than in the flexion and extension quadrants. The oblique planes of the circumduction curves of all the normal wrists lie in ulnopalmar and radiodorsal direction with a mean angle of 28° to the vertical flexion and extension plane. This technique was accurate and reliable in measuring the velocity, range, and smoothness of wrist circumduction.