Metacognition refers to students' knowledge and regulation of cognition, as well as their accuracy in predicting their academic performance. This study addressed two major questions: 1) how do metacognitive knowledge, regulation and accuracy differ across domains?, and 2) how do students' individual differences relate to their reported metacognition across domains? Participants (N = 644) completed a metacognitive questionnaire to assess metacognitive knowledge, regulation, and accuracy. Results suggest that metacognitive knowledge and regulation are domain-general while metacognitive accuracy is domain-specific. Perceived task difficulty and content interest are independently related to metacognitive knowledge, regulation, and accuracy, though the relationships vary among them across domains. (Contains 7 tables.)