This article maps out how people in queer communities on Reddit navigate context collapse. Drawing upon data from interviews with queer Reddit users and insights from other studies of context collapse in digital media, we argue that context collapse also occurs in anonymity-based social media. The interviews reveal queer Reddit users' practices of context differentiation, occurring at four levels: somatic, system, inter-platform and intra-platform. We use these levels to map out how lesbian, gay, bisexual, transgender and queer or questioning (LGBTQ) people express their identities and find community on Reddit while seeking to minimize the risks imposed by multiple impending context collapses. Because living an authentic queer life can make subjects vulnerable, we find that despite Reddit's anonymity, sophisticated practices of context differentiation are developed and maintained. We argue that context collapse in an era of big data and social media platforms operates beyond the control of any one user, which causes problems, particularly for queer people.