The purpose of this study to develop software to extract and investigate the rofiles of the tube current and volume computed tomography dose index (CTDI<sub>vol</sub>) along the longitudinal axis (z-axis). The tube current and CTDI<sub>vol</sub> were extracted from the Digital Imaging and Communications in Medicine (DICOM) header of every image along the longitudinal axis. We evaluated the profiles of the tube current and CTDI<sub>vol</sub> from eight computed tomography (CT) scanners. If the CTDI<sub>vol</sub> did not fluctuate along the fluctuation of the tube currents, then the system will adjust the CTDI<sub>vol</sub> with tube currents. It is found that TCM is not always activated. If TCM is activated, the profiles of TCM vary from one scanner to another. The Siemens and Philip scanners have adjusted the CTDI<sub>vol</sub> profile with tube current, but the Toshiba scanner has not. By developed software, CTDI<sub>vol</sub> profile of the Toshiba can be easily adjusted. In conclusion, software to investigate the profile pattern of CTDI<sub>vol</sub> along the longitudinal axis has been successfully developed. The software is easy to use and works quickly. From this study, medical staff must be careful when using the CTDI<sub>vol</sub> along longitudinal axis contained in each DICOM header.