Language users at level C1 are independent. They can express themselves fluently and spontaneously. They have a large vocabulary and can choose the appropriate expression to introduce their comments. They can produce clear, well-structured discourse without hesitation and which shows controlled use of structures.
C2 users' proficiency in the language is illustrated by precision, appropriateness and fluency of expression. C2 candidates are capable of using the language for academic and advanced-level purposes.
More information: https://www.france-education-international.fr/en/dalf/detailed-information-on-the-examinations