Tool
The harmonic field of D♭ major 5 flats in the key signature. Click a degree to hear it, or hear the whole field.
Triads D ♭ I Tonic Diatonic E ♭ m ii Subdominant Diatonic F m iii Tonic Diatonic G ♭ IV Subdominant Diatonic A ♭ V Dominant Diatonic B ♭ m vi Tonic Diatonic C dim vii° Dominant Diatonic
Degree Symbol Notes Function I D ♭ D♭ · F · A♭ Tonic ii E ♭ m E♭ · G♭ · B♭ Subdominant iii F m F · A♭ · C Tonic IV G ♭ G♭ · B♭ · D♭ Subdominant V A ♭ A♭ · C · E♭ Dominant vi B ♭ m B♭ · D♭ · F Tonic vii° C dim C · E♭ · G♭ Dominant
Seventh chords D ♭ maj7 Imaj7 Tonic Diatonic E ♭ m7 ii7 Subdominant Diatonic F m7 iii7 Tonic Diatonic G ♭ maj7 IVmaj7 Subdominant Diatonic A ♭ 7 V7 Dominant Diatonic B ♭ m7 vi7 Tonic Diatonic C m7 ♭5 viiø7 Dominant Diatonic
Degree Symbol Notes Function Imaj7 D ♭ maj7 D♭ · F · A♭ · C Tonic ii7 E ♭ m7 E♭ · G♭ · B♭ · D♭ Subdominant iii7 F m7 F · A♭ · C · E♭ Tonic IVmaj7 G ♭ maj7 G♭ · B♭ · D♭ · F Subdominant V7 A ♭ 7 A♭ · C · E♭ · G♭ Dominant vi7 B ♭ m7 B♭ · D♭ · F · A♭ Tonic viiø7 C m7 ♭5 C · E♭ · G♭ · B♭ Dominant
The notes are spelled in octave 4, from D♭4. The function is assigned by degree — tonic on I, III and VI; subdominant on II and IV; dominant on V and VII — which is how the harmonic field is taught. Context can change that reading, and the tool reports the degree.
Related keys B♭ minor Relative: the same key signature, in the other mode. C♯ minor Parallel: the same tonic, in the other mode. D♭ in the dictionary The tonic triad: notes, staff, keyboard and guitar shapes. Read about Diatonic harmony The chords that arise from stacking thirds on each degree of a scale, and why each quality lands where it does. Harmonic function The role each degree plays — tonic, subdominant, or dominant — and the tension that moves one to the next. Roman numeral analysis The notation that describes a chord by the position it occupies in the key rather than by the note it sits on. Minor key harmony The minor harmonic field, which is not one field: the three minor scales produce different chords on the same degree. 
