C half diminished scale
The C half diminished scale consists of the C (Perfect unison), D (Major second), D# (Minor third), F (Perfect fourth), F# (Diminished fifth), G# (Minor sixth) and A# (Minor seventh) notes.

How to play the C half diminished scale
- Find C (Root) on the piano keyboard
- Play D (Major second) — 2 semitones above C
- Play D# (Minor third) — 3 semitones above C
- Play F (Perfect fourth) — 5 semitones above C
- Play F# (Diminished fifth) — 6 semitones above C
- Play G# (Minor sixth) — 8 semitones above C
- Play A# (Minor seventh) — 10 semitones above C
- Play all 7 notes in ascending order to perform the C half diminished scale