Facebook friends, subjective well-being, social support, and personality

•Facebook (FB) network size was related to Life satisfaction and Happiness.•The results replicated across US and German samples.•The results replicated across various self- and other-ratings of well-being.•Number of FB friends was not associated with social support.•FB Network size could not predict well-being when Extraversion was controlled for.

Offline social capital in the form of interpersonal networks is known to be associated with subjective well-being (SWB). In two studies run in the US (N = 153) and Germany (N = 187), we initially investigated whether the size of an individual's Facebook social network was associated with SWB and perceived social support. Objectively measured Facebook network size was positively associated with several measures of both self- and informant rated SWB but not with perceived social support. More pertinent to the present research, we next investigated whether the observed associations between network size and SWB were, in fact, an artifact of personality – trait Extraversion in particular. Indeed, self- and informant-rated Extraversion was associated with both Facebook social network size and with self- and informant-rated SWB. Importantly, controlling for Extraversion rendered the associations between Facebook social network size and SWB weak and statistically insignificant. We discuss the importance of social relationships on Facebook for well-being, as well as the implications of our results for research on the relationship between SWB, social network size, and personality.