How objective is our perception of gender, as measured against the binary gender system? This interactive installation confronts visitors with this very question, comparing their assessments of real-world social distributions with empirical data. Based on these discrepancies, an individual bias score is calculated, revealing the strength and direction of gender-specific biases. CODE XX/XY demonstrates how one's perception can be shaped by implicit assumptions and societal narratives, and how neutral it is. It invites visitors to question their perception of reality, providing a starting point for gaining insight.