The article discusses the main studies of the mass/crowd social action in the digital space. The author compares classical social and philosophical mass analysis of society (XX century) and innovations by theorists of a digital society (XXI century). The author’s aim is to substantiate the new concept of mass in the digital society. The author analyzes the socio-philosophical concepts of the masses in the Internet space. The practice of mass social networking is widespread on the Internet. Their distinctive feature is a rational basis. Social theorists note this fact and begin the philosophical rethinking of the role of the crowd in the social system. The transition from the negative perception of the crowd to its actual «rehabilitation» starts. The result is the recognition of the rationality of social actions of the crowd. New forms of social interaction have changed the nature of social consolidation and digital solidarity. The ideological foundations of solidarity are the thing of the past. Digital ways of large people masses unification, the priority of personal social connections and network actions rise. The author offers the definition of a digital crowd and reveals its main features: increase of its management efficiency, strengthening of cognitive potential, distribution of available resources for the solution for important social tasks.