C♯m7♭5
C♯ Half-Diminished
1 ♭3 ♭5 ♭7

Notes in C♯m7♭5

C♯R
E♭3
G♭5
B♭7

The C♯m7♭5 chord contains 4 notes: C♯, E, G, B

Intervals

IntervalSemitonesNoteFunction
R0C♯Root
♭33EMinor 3rd
♭56GDiminished 5th
♭710BMinor 7th

About C♯ Half-Diminished Chords

Half-diminished chords (minor 7 flat 5) combine a diminished triad with a minor 7th. They serve as the ii chord in minor key ii-V-i progressions, making them essential for jazz musicians. The sound is dark but more stable than fully diminished.

Compatible Scales & Modes

These scales contain all the notes of C♯m7♭5 and can be used for soloing, improvising, and writing melodies over this chord.

C♯ Locrian
The natural mode for half-diminished chords — every chord tone is a scale tone.
C♯ Locrian ♯2
A common jazz alternative — the natural 2nd adds melodic possibilities.

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Playing C# half-diminished on Guitar

The C# half-diminished chord, spelled C♯, E, G, B, occupies a specific harmonic role that depends on the musical context. In the key of Db major enharmonically, this chord can function as a primary harmony or as a passing color depending on where it appears in the progression. Understanding which scale degrees produce C#-rooted chords helps you predict chord progressions and improvise melodies that complement the harmony.

On guitar, C# half-diminished voicings benefit from fourth-fret barre shapes that provide a bright, cutting tone. The physical shape of this chord on the fretboard determines its tonal character — the same notes arranged in different voicings produce noticeably different sounds due to string gauge, fret position, and overtone content. Experiment with playing C# half-diminished in multiple positions to find the voicing that best fits the register and texture of the music you are working on.

C#m7b5, also called C# half-diminished, is built by adding a minor seventh to a diminished triad. This chord naturally occurs on the seventh degree of major keys and the second degree of minor keys, making it essential for minor key ii-V-i progressions in jazz.

When practicing C# half-diminished, use the compatible scales listed above to improvise melodies and riffs. Start by playing the chord, then explore the scale tones one at a time to hear how each note sounds against the harmony. This ear training exercise connects your theoretical knowledge of C#-rooted chords to practical musicianship skills that improve your playing across all genres and styles.