Objective: We aimed to examine the psychometric properties of the Scale of Perfectionism and Excellencism (SCOPE) in a novel sample, Australian adolescents. Method: The cross-sectional sample consisted of 350 participants (79 male, 271 female; mean age 17.9 years, age range = 15-20 years) from a secondary 10 school and university who completed a web-based questionnaire. Results: Confirmatory factor analyses showed that the original two-factor structure was replicated and invariant across gender, educational setting, and language (English as first or second language). Cronbach alphas indicated good internal consistency: Excellencism (0.95) and Perfectionism (0.97). We found evidence for divergent and convergent validity. Academic performance was associated with Excellencism, independent of 15 Perfectionism (partial r = 0.32; p < 0.01), with no discernible relationship with Perfectionism. We explored concurrent validity and found mixed results with associations being in the expected direction only for the criterion measures that might be conceptualised as capturing negative-type perfectionism. Conclusions: This study provides valuable insights into SCOPE and the distinct constructs of Excellencism and Perfectionism. Findings indicate Excellencism is associated with more positive 20 academic and mental health outcomes compared to Perfectionism. Further research is warranted to explore long-term outcomes of these constructs to potentially inform educational practice, mental health promotion, and early intervention.