C♯ 7th flat 5 chord on ukulele (C♯7♭5)

Also called or written C♯7♭5, C♯, C♯ Dominant 7th Flat 5 or C♯ 7th ♭5

C♯ 7th flat 5 is built from C♯, E♯, G, and B. The 6th fret shape stacks three fingers in a row before the pinky reaches fret 8.

6frC♯GBE♯GCEA
Positions on the neck1 of 4
Practice C♯ 7th flat 5 chord

How it is built

C♯RootE♯Major thirdGDiminished fifthBMinor seventh

Formula 1, 3, ♭5, ♭7

Inversions

How do you play a C♯ 7th flat 5 chord on ukulele?

C♯ 7th flat 5 is played at the 6th fret as 6 7 7 8: index finger on the G string at fret 6, middle finger on the C string at fret 7, ring finger on the E string at fret 7 and pinky finger on the A string at fret 8.

Full note and interval breakdown
StringFretFingerNote
4 (G)61C♯ (1)
3 (C)72G (♭5)
2 (E)73B (♭7)
1 (A)84E♯ (3)

AdvancedThe pinky must reach fret 8 cleanly while the ring finger holds fret 7 on the E string.

C♯7♭5/B inversion

C♯ 7th flat 5 is played at the 9th fret as 10 11 9 10: middle finger on the G string at fret 10, pinky finger on the C string at fret 11, index finger on the E string at fret 9 and ring finger on the A string at fret 10.

Full note and interval breakdown
StringFretFingerNote
4 (G)102E♯ (3)
3 (C)114B (♭7)
2 (E)91C♯ (1)
1 (A)103G (♭5)

Open

C♯ 7th flat 5 is played in open position as 0 1 1 2: index finger on the C string at fret 1, middle finger on the E string at fret 1 and ring finger on the A string at fret 2. The G string rings open.

Full note and interval breakdown
StringFretFingerNote
4 (G)openG (♭5)
3 (C)11C♯ (1)
2 (E)12E♯ (3)
1 (A)23B (♭7)

C♯7♭5/E♯ inversion

C♯ 7th flat 5 is played at the 3rd fret as 4 5 3 4: middle finger on the G string at fret 4, pinky finger on the C string at fret 5, index finger on the E string at fret 3 and ring finger on the A string at fret 4.

Full note and interval breakdown
StringFretFingerNote
4 (G)42B (♭7)
3 (C)54E♯ (3)
2 (E)31G (♭5)
1 (A)43C♯ (1)

Why it sounds like that

C♯ 7th flat 5 uses the formula 1, 3, ♭5, ♭7. The diminished 5th between C♯ and G gives the chord its tense color. Compare it to C♯ 7th, which raises that G to G♯.

What goes wrong with C♯ 7th flat 5?

  • Letting the pinky flatten onto the A string, which buzzes the note.
  • Pressing the ring finger too far across, deadening the C string.
  • Strumming before the middle finger is fully seated on the C string.

When to use it

C♯ 7th flat 5 works as a tense dominant in C♯ major, especially moving to C♯ major or C♯ 5th. Its altered fifth suits jazz and funk lines where a plain C♯ 7th sounds too settled.

Changing to and from C♯ 7th flat 5

  • Sliding the shape down two frets to the 4th fret gives B 7th flat 5.
  • Sliding the shape up one fret to the 7th fret gives D 7th flat 5.

Which voicing to use

The 6th fret position keeps C♯ in the bass for a root-position sound. The C♯7♭5/E♯ inversion at the 10th fret puts the major third in the bass, while the C♯7♭5/G inversion at the open position emphasizes the ♭5.

Other C♯ chords

Common questions

How is C♯ 7th flat 5 written?

C♯ 7th flat 5 is written as C♯7♭5 or C♯. The symbol C♯7♭5 is the most common, and the ASCII root is C#. It is also spelled D♭ in enharmonic notation for the same sounding root.

What is the difference between C♯ 7th flat 5 and C♯ 7th?

C♯ 7th flat 5 lowers the fifth from G♯ to G, creating a diminished fifth. C♯ 7th keeps the perfect fifth G♯.

Why does C♯ 7th flat 5 sound unstable?

The diminished fifth between C♯ and G is a tritone, which wants to resolve. This tension makes the chord useful before a tonic.