C half-diminished (Cm7b5) chord on guitar

The C half-diminished chord (Cm7b5) is a half-diminished seventh chord (a diminished triad plus a minor seventh), made of four notes: C – E♭ – G♭ – B♭.

Dots show:

Position 1medium

A shape, fret 3medium

Position 6medium

E shape, fret 8hard

D shape, fret 10medium

Position 13medium

Tap a string on a diagram to hear just that string. The sound is generated in your browser with a physical string model.

Chord finder Transposer Tuner

What the Cm7b5 chord sounds like

The half-diminished (m7b5) chord is a diminished triad with a minor seventh. In a minor key it sits on degree ii – the first chord of the minor ii–V–i.

Notes of the Cm7b5 chord

Degree	Note	Interval from the root
1	C	root
3	E♭	minor third (3 semitones)
5	G♭	diminished fifth (6 semitones)
7	B♭	minor seventh (10 semitones)

How to play it – with fingering

Position 1, barre at fret 1

String 1 (e): fret 2, middle finger (G♭4)
String 2 (B): fret 1, index finger (C4)
String 3 (G): fret 3, little finger (B♭3)
String 4 (D): fret 1, index finger (E♭3)
String 5 (A): fret 3, ring finger (C3)
String 6 (E): not played

For the barre, lay your index finger flat across all the marked strings at fret 1; your other fingers press the higher frets.

A shape, fret 3

String 1 (e): not played
String 2 (B): fret 4, little finger (E♭4)
String 3 (G): fret 3, middle finger (B♭3)
String 4 (D): fret 4, ring finger (G♭3)
String 5 (A): fret 3, index finger (C3)
String 6 (E): not played

Position 6

String 1 (e): not played
String 2 (B): fret 7, middle finger (G♭4)
String 3 (G): fret 8, little finger (E♭4)
String 4 (D): fret 8, little finger (B♭3)
String 5 (A): fret 6, index finger (E♭3)
String 6 (E): fret 8, ring finger (C3)

The “C, A, G, E and D shapes” are the CAGED system: you slide the shape of the open C, A, G, E or D chord up the neck and your index finger (a barre) takes over the job of the nut. That way the same chord can be played in five places, anywhere on the fretboard.

Tuning: E A D G B E (low to high). String 6 is the thickest, the low E. In the diagram, × means the string is not played, and a circle means an open string.

Playing Cm7b5 with a capo

A capo clamps all the strings at one fret, so a familiar open shape sounds higher. You can also get a Cm7b5 chord with these open shapes:

Capo: fret 1
shape: Bm7b5

Capo: fret 3
shape: Am7b5

Rework a whole song for a capo: chord transposer →

Which keys is it in?

The Cm7b5 chord is built from the notes of these keys (for minor keys, both the natural and the harmonic minor are considered):

D♭ major: viiø7
B♭ minor: iiø7

Similar chords and substitutes

If Cm7b5 is too hard, or you want a different colour in the same spot, these chords are worth a try.

Substitutes (by function)

A♭9 – a rootless dominant ninth: the same notes over a root a major third lower
F7 – the next chord in a minor ii–V–i (V)

Same notes

E♭m6 – the same notes with a different root

Simpler versions

Cdim – all 3 of its notes are in this chord

Frequently asked questions

What notes are in the Cm7b5 chord?

C, E♭, G♭, B♭. The root is C; the intervals of the other notes from the root: minor third, diminished fifth, minor seventh.

What is the easiest way to play Cm7b5 on guitar?

The easiest shape above is “Position 1”. We show 6 shapes, from open and easy versions to movable barre shapes higher up the neck. With a capo you can also play it as a Bm7b5 shape at fret 1 or a Am7b5 shape at fret 3.

How do I read the chord diagram?

Strings run from the lowest (left) to the highest (right) – tick “Left-handed” to mirror it. Rows are frets; a number at the side shows the starting fret. Dots are fingers (1 index, 2 middle, 3 ring, 4 little), a long bar is a barre, × means don't play that string and ○ means play it open.

How is the Cm7b5 chord written?

The chord symbol is Cm7b5, and its full name is C half-diminished.