To classify how well somebody can handle a language there are different levels:
A1 – making use of everyday expressions being able to comprehend and use simple phrases
A2 – being able to understand and use simple phrases and frequently used expressions and to communicate in simple situations
B: Speaking independently
B1 – being able to understand key points when standard language is used on familiar subjects, such as work, school, leisure. Speaking about simple and coherently about familiar subjects and personal fields of interest.
B2 – Understanding central statements of complex texts on concrete and abstract issues. Being able to communicate spontaneously and fluently in a way that a conversation with a native speaker is possible without much effort on both sides.
C: Advanced speaking
C1 – Comprehending a wide range of challenging, longer texts. Using language effectively in professional life.
C2- Almost perfect use of language!