C diminished major 7th chord on ukulele (CdimMaj7)

Also called or written CdimMaj7, CdimM7, C°M7, C augmented minor seventh or C minor seventh sharp five

C diminished major 7th contains C, E♭, G♭ and B. The 5th fret shape is the same four-finger stretch as A, moved up three frets.

5frCG♭BE♭GCEA
Positions on the neck1 of 2
Practice C diminished major 7th chord

How it is built

CRootE♭Minor thirdG♭Diminished fifthBMajor seventh

Formula 1, ♭3, ♭5, 7

Inversions
  • Root positionC–E♭–G♭–BCdimMaj75-6-7-6
  • First inversionE♭–G♭–B–CCdimMaj7/E♭4-3-2-3
  • Second inversionG♭–B–C–E♭CdimMaj7/G♭5-6-7-6
  • Third inversionB–C–E♭–G♭CdimMaj7/B4-3-2-3

How do you play a C diminished major 7th chord on ukulele?

C diminished major 7th is played at the 5th fret as 5 6 7 6: index finger on the G string at fret 5, middle finger on the C string at fret 6, pinky finger on the E string at fret 7 and ring finger on the A string at fret 6.

Full note and interval breakdown
StringFretFingerNote
4 (G)51C (1)
3 (C)62G♭ (♭5)
2 (E)74B (7)
1 (A)63E♭ (♭3)

AdvancedThe pinky must stretch to fret 7 on the E string while the ring finger holds fret 6 on the A string.

CdimM7/E♭ inversion

C diminished major 7th is played at the 2nd fret as 4 3 2 3: pinky finger on the G string at fret 4, middle finger on the C string at fret 3, index finger on the E string at fret 2 and ring finger on the A string at fret 3.

Full note and interval breakdown
StringFretFingerNote
4 (G)44B (7)
3 (C)32E♭ (♭3)
2 (E)21G♭ (♭5)
1 (A)33C (1)

Why it sounds like that

C diminished major 7th is built 1, ♭3, ♭5, 7. The diminished 5th between C and G♭ is a tritone, and the major 7th B is a leading tone to C. Compare it with C minor 7th flat 5th, which has B♭ instead of B.

What goes wrong with C diminished major 7th?

  • Letting the pinky mute the A string by flattening.
  • Pressing the middle finger too far from the fret, causing the C string to buzz.

When to use it

C diminished major 7th works as a passing chord in C minor, resolving to C minor or C major. Its leading tone suits jazz and whole-half scale runs.

Changing to and from C diminished major 7th

  • Slide the shape down one fret to the 4th fret to reach B diminished major 7th.

Which voicing to use

The 5th fret position keeps C in the bass. The CdimM7/B inversion puts B in the bass, creating a tense sound with the leading tone on the bottom.

Other C chords

Common questions

How is C diminished major 7th written?

C diminished major 7th is written C°M7 or CdimM7.

What is the difference between C diminished major 7th and C minor 7th flat 5th?

C diminished major 7th has a major 7th, B. C minor 7th flat 5th has a minor 7th, B♭.

How does this supplied chord create its distinctive sound?

C diminished major 7th uses G♭ because the diminished 5th from C is six semitones, and G♭ is the correct spelling in a C context.