The CEFR Levels are a way of describing a person’s level of English. They are getting more and more popular all the time.
There are six CEFR levels: A1, A2, B1, B2, C1, C2. A1 is the lowest and C2 is the highest.
See a summary of the levels here:http://roadtogrammar.com/tools/CEFR/
Or click on the image below to enlarge it: