Introduction: Assessment of testicular size is an essential and initial method for the evaluation of testicular function. For accurate measurement of testicular volume, ultrasonography is considered as most crucial radiological technique. Our study aims to determine variations in testicular volumes among healthy adults with the help of ultrasonography. Materials and Method: Our study was a prospective observational category study. It was carried out at the Department of Radiology, Chettinad Hospital and Research Institute, Kelambakkam, Chennai. This study was carried between August 2019 and August 2021. A total of 100 adult males aged 18 to 70 years were assessed to measure the testicular size, and Lambert’s formula was used to calculate testicular volumes on both sides. The relationship between testicular volumes, anthropometric measurements and other characteristics of participants were also evaluated. Results: Lambert’s formula was used, and the testicular volumes were determined. A total number of 100 adult males aged 18 to 70 years (median age 38 years) participated in this study. The mean testicular volume was recorded as 21.97 ± 5.89 cm3 and 23.58 ± 5.62 cm3 on the right and left sides of the testis, respectively. The differences on both sides of the volumes were statistically significant. There was also a statistically significant correlation between age, testicular volumes, right length, left length and left testicular width. Conclusions: The result from the present study shows that ultrasonography was the most accurate method for measuring the testicular volume and evaluating gonadal functions.