The following five German language tests and certificates must be recognized by all German universities:
- TestDaF (TDN 3, 4 or 5) (Test Deutsch als Fremdsprache)
- DSH II or III (Deutsche Sprachprüfung für den Hochschulzugang)
- Goethe-Zertifikat C2
- telc Deutsch C1 Hochschule (The European Language Certificate)
- DSD II (Deutsches Sprachdiplom Stufe II)
In a Resolution of the Standing Conference of the Ministers of Education and Cultural Affairs (KMK) in Germany, all five of them were defined as equally valid when it comes to applying to German universities. So as long as you hold one of these certificates, you are good. The university of your choice will accept your certificate as valid proof of your language skills.
Each program can decide on a level of German skills independently. Therefore, the minimum results in each language test required from you vary from university to university.