The CEFR describes foreign language proficiency at six levels: A1 and A2, B1 and B2, C1 and C2. It also defines three ‘plus’ levels (A2+, B1+, B2+). Based on empirical research and widespread consultation, this scheme makes it possible to compare tests and examinations across languages and national boundaries (see the section “The CEFR and language examinations: a toolkit”). It also provides a basis for recognising language qualifications and thus facilitating educational and occupational mobility.
Complete Persian translation: http://languageties.com/fa/article/cefr