Common European Framework of Reference for Languages (CEFR)
The Common European Framework of Reference for Languages: Learning, Teaching, Assessment, abbreviated as CEFR, is a guideline used to describe achievements of learners of foreign languages across Europe and, increasingly, in other countries. It was developed by the Council of Europe as core result of the project "Language Learning for European Citizenship" between 1989 and 1996. It aims to provide a method of learning, teaching and assessment which applies to all languages in Europe. In November 2001 a European Union Council Resolution recommended to use the CEFR to set up systems of validation of language competences. The six reference levels are widely accepted as the European standard for describing individual language proficiency.
https://www.coe.int/en/web/common-european-framework-reference-languages