This paper proposes a telemedicine tool (complete of hardware, software and 3D printed face mask) for analyzing exhaled carbon dioxide (CO2) levels. Our interest in CO2 pattern is due to its correlation to psychological and physiological health status. To achieve this information, we developed a customized printed circuit board equipped with a CO2 sensor for breath analysis, a microcontroller, a WiFi module for data transmission, and a battery for enabling an autonomous device. We also developed an interactive web page for the users and a database for daily remote data management. The device was tested on two healthy subjects of different ages and with different lifestyles. The results highlighted that the younger subject presents increased CO2 values as a direct link to a more active life. We consider these promising results for testing our device on a major cohort of observational studies.