Format, the B1 rule, and each part are on the DTZ B1 page.
Quick Answer
The DTZ is administered at licensed test centres (Prüfstellen) authorised by the Federal Office for Migration and Refugees (BAMF) and connected to g.a.s.t. You book and register with the centre you choose; g.a.s.t. centralises materials and scoring. The exam room is the one on your Prüfstelle confirmation. Locate providers through BAMF’s public navigation. Eight cities named for inspecting your marked papers after a result are a separate list for Einsicht, not a map of every exam location.
How BAMF licensing fits the DTZ
g.a.s.t. describes nationwide delivery with central marking while Prüfstellen remain the local operators. Use BAMF’s public navigation to locate providers in your state, then email or visit the centre that actually lists DTZ sessions. A training school with no DTZ slot is not a workaround.
Inspection cities are not the exam network
If you need to see marked papers after results, g.a.s.t. schedules fixed Einsicht appointments in eight cities (Chemnitz, Berlin, Wedel, Hildesheim, Dortmund, Bingen am Rhein, Augsburg, Nürnberg — postal codes appear in the FAQ). That service does not mean your exam was offered in those places. Keep the two lists separate when you plan travel.
Pick a centre, then rehearse once
After the Prüfstelle confirms your session, walk the DTZ B1 mock test landing so Hören/Lesen timing, paired Sprechen, and Schreiben sheet rules feel familiar before you commit travel time.