The GAT-TO online tutorial and the editor are helpful tools for digital transcription. Phonetische Transkription des Deutschen
Phonetische Transkription des Deutschen: Ein Arbeitsbuch is a standard reference with audio examples and exercises. Phonetische Transkription des Deutschen
[aː], [a], [eː], [ɛ], [iː], [ɪ], [oː], [ɔ], [uː], [ʊ], [yː], [ʏ], [øː], [œ]. The GAT-TO online tutorial and the editor are