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Chord chart for Co7 Guitar Chord (C diminished 7th): Notes, Shapes & How to Play | Guitar Wiz

C diminished 7th guitar shapes

Popular fretboard positions with fingering suggestions

Showing 8 of 15 playable shapes

C diminished 7th guitar chord diagram showing fretboard positions
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About the chord

C diminished 7th guitar chord

Co7 is the C diminished 7th guitar chord. It uses the notes C, E♭, G♭, and B♭♭ and the interval formula 1-♭3-♭5-♭♭7.

The C diminished 7th diminished 7th chord extends the diminished triad with a double-flatted seventh B♭♭, creating a haunting, symmetrical dissonance. Its ambiguous, tension-filled sound is ideal for dramatic resolutions, suspenseful scenes, or mysterious soundscapes in classical and cinematic compositions.

Also written as Cdim7.

Root note: C
Quality: diminished 7th
Chord tones: 4
Playable shapes: 15

Chord tones

CE♭G♭B♭♭

Common guitar voicings

These are quick-start shapes for players who want the answer first and the deeper theory second.

Shape 1

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  1. 1 Place the 1st finger on the 2nd fret of the 1st string and 3rd string in barre position.
  2. 2 Place the 2nd finger on the 3rd fret of the 5th string.
  3. 3 Place the 3rd finger on the 4th fret of the 4th string.
  4. 4 Place the 4th finger on the 4th fret of the 2nd string.
  5. 5 Strum from the 5th string down.

Shape 2

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  1. 1 Place the 1st finger on the 7th fret of the 2nd string and 4th string in barre position.
  2. 2 Place the 2nd finger on the 8th fret of the 6th string.
  3. 3 Place the 3rd finger on the 8th fret of the 3rd string.
  4. 4 Place the 4th finger on the 8th fret of the 1st string.
  5. 5 Strum from the 6th string down.

Notes & Intervals

Each note below shows how the chord is built from its root. This is the theory layer underneath the fretboard shapes.

C Unison (Root) 1

The root anchors the chord and defines its tonal center.

E♭ Minor Third ♭3

This note supplies the minor color and gives the chord its darker emotional pull.

G♭ Diminished Fifth ♭5

The flattened fifth adds tension and a restless, unstable edge.

B♭♭ Diminished Seventh ♭♭7

The diminished seventh heightens instability and gives the chord a tense symmetrical quality.

Quick answers

What notes are in Co7?

Co7 uses the notes C, E♭, G♭, and B♭♭. Its interval formula is 1-♭3-♭5-♭♭7.

What is another name for Co7?

Co7 is also written as Cdim7.

How do you play Co7 on guitar?

Place the 1st finger on the 2nd fret of the 1st string and 3rd string in barre position. Place the 2nd finger on the 3rd fret of the 5th string. Place the 3rd finger on the 4th fret of the 4th string. Place the 4th finger on the 4th fret of the 2nd string. Strum from the 5th string down.

Related Articles

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