Social media are becoming increasingly popular in a professional context and, if used appropriately, can be beneficial to postgraduate students. Little is known regarding the extent to which postgraduate students engage with social media for postgraduate purposes. The present study aimed to understand postgraduate students' general use of social media, as well as investigate social media use specifically for postgraduate (educational and/or scientific) purposes. A total of 231 postgraduate students from 45 countries completed a mixed-methods survey. Instagram was the most frequently used social media platform overall, with Twitter being the most commonly used for postgraduate purposes. Most students posted educational and/or scientific content on social media platforms, with approximately one-third having a social media account specific for postgraduate/scientific content. The most common reasons postgraduate students access social media for postgraduate-related purposes were personal connection with community, science communication, motivations and learning, and networking. The most common reasons for posting postgraduate content online were self-branding, accessing a broad audience, science communication, and building a postgraduate community. Overall, postgraduate students are commonly using social media for postgraduate purposes which presents opportunities to mitigate pitfalls of the student experience and promote positive mental health among this group.