| Stage | Level | Official Class Name |
| Beginner | Level 1 | B 1 |
| Level 2 | A 1 | |
| Elementary | Level 3 | B 2 |
| Level 4 | A 2 | |
| Pre-intermediate | Level 5 | B 3 |
| Level 6 | A 3 | |
| Intermediate | Level 7 | B 4 |
| Level 8 | A 4 | |
| Upper-intermediate | Level 9 | B 5 |
| Level 10 | A 5 | |
| Advanced | Level 11 | B 6 |
| Level 12 | A 6 |