Levels

A1 (Breakthrough or beginner) student will be able to:

Understand and use basic phrases and word combinations to express specific needs;
Introduce him/herself and others;
Form questions and answers about him/herself and others, e.g. where he/she lives, people he/she knows and things he/she has;
Interact with people speaking English under the condition that they speak slowly, clearly and are ready to help.

A2 (Waystage or elementary) student will be able to:

Understand sentences and frequently used expressions related to areas of most immediate relevance (e.g. very basic personal and family information, shopping, local geography, employment)
Communicate in basic and routine tasks requiring a simple and direct exchange of information on familiar and routine matters
Can describe in basic terms aspects of his/her background, immediate environment and matters in areas of immediate need

B1 (Threshold or intermediate) student will be able to:

Acquire understanding of the main issues of clear and typical information about current affairs in familiar sphere at work, at school, in his/her free time, etc;
Work their way out of possible situations that may occur in a foreign country while abroad;
Express himself/herself using simple connected sentences of familiar topics or personal interests;Speak about personal experience, events, dreams, expectation and ambitions, and also speak shortly about his/her plans for the future.

B2 (Threshold or intermediate) student will be able to:

Understand the main ideas of complex text on both concrete and abstract topics, including technical discussions in his/her field of specialization;
Interact with a degree of fluency and spontaneity that makes regular interaction with native speakers quite natural and without confusion from either party;
Produce clear, detailed text on a wide range of subjects and express a viewpoint on a topical issue while discussing the advantages and disadvantages of various options.

C1 (Effective Operational Proficiency or advanced) student will be able to:

Understand a wide range of demanding, lengthy texts, and recognize implicit meanings;
Express him/herself fluently and spontaneously without much obvious searching for expressions;
Use language flexibly and effectively for social, academic and professional purposes;
Produce clear, well-structured, detailed text on complex subjects, showing controlled use of organizational patterns, connectors and cohesive devices.

C2 (Mastery or proficiency) student will be able to:

Understand with ease virtually everything heard or read;
Summarize information from different spoken and written sources, reconstructing arguments and accounts in a coherent presentation;
Express him/herself spontaneously, very fluently and precisely, recognizing nuances of meaning even in the most complex situations.

Deutsche Welle magazine (sponsored by the German government) has calculated that

The description is used for any European language.