The economic literature on the superstar phenomenon provides empirical evidence on different types of stars, above all athletes and musicians. A new and, to our best knowledge, unexplored area of this star theory arouse with the development of social media markets. In this paper, we analyse a unique sample of 200 YouTube stars out of four different video categories to address the research gap. By employing econometric methods from panel data analysis, we contribute to answering the following research questions: (i) Are the classic theoretical concepts of popularity and superstardom by Rosen, MacDonald and Adler applicable? (ii) Can social media stars actively influence their popularity by employing special upload strategies? We find empirical evidence that former success positively and significantly influences the current success of social media stars, as theoretically presumed by MacDonald. Furthermore, the results support Adler’s assumptions that the most popular stars snowball into superstardom due to higher growth rates. Finally, our investigation shows that social media stars can actively influence their popularity with distinctive upload strategies and market behaviour.