Chord · 7ths

C♯m7♭5 — C♯ Half-Diminished

C♯m7♭5 is the C♯ half-diminished chord. It is built on the root C♯ with minor 3rd (E), diminished 5th (G) and minor 7th (B) above it — the formula 1 ♭3 ♭5 ♭7, sounding the notes C♯ E G B. On the piano it sits at C# (octave 4) and above in the library's voicing; the same 4 notes in any octave are still C♯m7♭5.

Root
C♯
Quality
Half-Diminished
Formula
1 ♭3 ♭5 ♭7
Notes
C♯ E G B

On the keyboard

C♯m7♭5 on the piano keyboard: C♯ E G B1235C♯EGB

Right-hand fingering for this voicing: 1–2–3–5 (1 is the thumb).

The notes of C♯m7♭5

DegreeNoteInterval from the rootPitch
1C♯rootC♯4
♭3Eminor 3rdE4
♭5Gdiminished 5thG4
♭7Bminor 7thB4

Other 7ths on C♯

Half-Diminished chords on every root

Part of the chord reference. See also the scales and the keys.