The aim of this study is to determine and evaluate the activity of over 200 German universities on social media using an index. The University Social Media Index is created through a weighted additive index (Min: 0 points, Max: 100 points). The weights are assessed based on the usage rates of the social media platforms prevalent in Germany and the level of potential social interaction activity of the platforms in the form of a scoring model. Accordingly, the study focuses on the social media platforms Facebook, Twitter, YouTube, Xing, as well as the integration of social buttons implemented on the homepages of the respective universities. The measurement of the values of the individual indicators was conducted on January 8, 2013. The social media platforms LinkedIn, Google+, and other social media networks are not included due to a lack of membership numbers.