C2 level Japanese is the highest level of proficiency in the Japanese language, requiring a full command of grammar, vocabulary, and idiomatic expressions. It can be measured using the Common European Framework of Reference for Languages (CEFR) and achieving this level has many personal and professional benefits. Achieving C2 level Japanese requires significant time and effort, including immersion in the language and culture. Resources such as textbooks, online courses, language exchange programs, immersion programs, and private tutoring are available to learners. Examples of C2 level proficiency include understanding complex conversations on any topic, reading a wide range of materials, expressing oneself accurately and fluently in both spoken and written forms, and appreciating Japanese culture deeply.