The rapid evolution of AI technologies has reshaped our daily lives. As AI systems become increasingly prevalent, AI literacy, the ability to comprehend and engage with these technologies, becomes paramount in modern society. However, existing research has yet to establish a comprehensive framework for AI literacy. This study aims to fill this gap by developing a holistic AI literacy scale. Three levels of dimensions are considered: individual, interactive, and sociocultural. The scale includes cognitive, behavioral, and normative competencies. After rigorous reliability and validity assessments, the final AI literacy scale comprises six dimensions: AI features, AI processing, algorithm influences, user efficacy, ethical consideration, and threat appraisal. Detailed scale development, validation, and dimension-specific items are thoroughly explained. This comprehensive scale equips individuals with the competencies needed to navigate and critically engage with AI in today's multifaceted AI landscape.