Studies report an increase in self‐harm, and engagement in risk content online has gained growing attention. This study aims to synthesize qualitative studies on youths' (12–25 years of age) engagement in self‐harm content online (SCO). We conducted a systematic database search of studies on first‐person experience and included 16 studies. The meta‐synthesis resulted in two meta‐themes: 1) “Belonging to a community – online engagement with peers who self‐harm” and 2) “Self‐development – online engagement to get to know myself”. Following Winnicott's (1953) thinking, digital activity is discussed as an extended peer arena with a “transitional” quality – neither completely internal, nor external, and potentially bridging an inner and outer world. Engagement in SCO is discussed as a transitional object or activity that enables relatedness and self‐definition – important developmental experiences for the exploration of social roles, borders between self and others and self‐identity during adolescence. However, engagement in SCO comes with a risk for deterioration of mental health. Clinicians should ask directly about digital activity and meet those engaged in digital risks with respect.