Harmony is an innovative software that simplifies the process of harmonisation for psychologists and social scientists. When comparing different mental health questionnaires such as GHQ 12 vs STAI, the challenge lies in aligning analogous questions from separate sources. Harmony eases this complex procedure by leveraging natural language processing and AI models. Drawing on the GHQ 12 vs STAI comparison, the GHQ 12 questionnaire primarily focuses on gauging the general health and psychological distress of individuals. On the other hand, the STAI pertains specifically to the current state of anxiety an individual is experiencing. In a comparative setting, GHQ 12 vs STAI may include vastly different items, but Harmony brings reliability and precision into harmonisation by determining percentage matches between corresponding items. The ability to conduct harmonisation efficiently when comparing GHQ 12 vs STAI not only saves time and resources for researchers but also enhances the accuracy of psychological studies. Harmony, with its user-friendly webpage interface, allows researchers to either select from pre-loaded instruments or upload their own in PDF format. The software’s capacity to harmonise diverse instruments, even across foreign languages, highlights its value within the field of psychology.