C-sharp dominant seventh chord (C#7)
The C♯ dominant seventh chord (C♯7) is a dominant seventh chord: a major triad with a minor seventh on top, C♯, E♯, G♯ and B (root, major third, perfect fifth and minor seventh).
It is the V7 in F♯ major and the V7 in F♯ minor, and it wants to resolve to F♯ major, a perfect fourth higher.
Below: voicings, notes on the fretboard, ukulele, piano, inversions and progressions.
How to play C♯ dominant seventh on guitar
There are 3 guitar voicings.
Frets from the 6th string to the 1st: x = not played, 0 = open string.
- Voicing 1: x-4-3-4-2-x, with C♯ in the bass (fingers x-3-2-4-1-x).
- Voicing 2: 9-11-9-10-9-9, movable E-shape barre chord at fret 9, with C♯ in the bass.
- Voicing 3: x-4-6-4-6-4, movable A-shape barre chord at fret 4, with C♯ in the bass.
Notes of the C♯ dominant seventh chord on the fretboard
C♯ dominant seventh has 4 notes: C♯, E♯, G♯ and B. This is where they fall on each string, from the nut to the 12th fret (fret number in parentheses):
- String 6 (E): E♯ (1) · G♯ (4) · B (7) · C♯ (9)
- String 5 (A): B (2) · C♯ (4) · E♯ (8) · G♯ (11)
- String 4 (D): E♯ (3) · G♯ (6) · B (9) · C♯ (11)
- String 3 (G): G♯ (1) · B (4) · C♯ (6) · E♯ (10)
- String 2 (B): B (0) · C♯ (2) · E♯ (6) · G♯ (9) · B (12)
- String 1 (E): E♯ (1) · G♯ (4) · B (7) · C♯ (9)
Formula and intervals of C♯ dominant seventh
Its formula is 1-3-5-♭7; in semitones from the root, 0-4-7-10.
- C♯: Root, the note that gives the chord its name
- E♯: Major third (M3), 4 semitones above C♯
- G♯: Perfect fifth (P5), 7 semitones above C♯
- B: Minor seventh (m7), 10 semitones above C♯
C♯ dominant seventh on ukulele
- Ukulele (G C E A): 1-1-1-2, barre at fret 1; it sounds G♯, C♯, E♯ and B.
C♯ dominant seventh on piano
- Keys: C♯4, E♯4, G♯4 and B4.
Inversions of C♯ dominant seventh
Each inversion puts a different note in the bass.
- Root position: C♯, E♯, G♯ and B, with C♯ in the bass.
- First inversion (C♯7/E♯): E♯, G♯, B and C♯, with E♯ in the bass.
- Second inversion (C♯7/G♯): G♯, B, C♯ and E♯, with G♯ in the bass.
- Third inversion (C♯7/B): B, C♯, E♯ and G♯, with B in the bass.
Keys that use C♯ dominant seventh
C♯ dominant seventh appears in 3 major and minor keys.
| Key | Degree | Function |
|---|---|---|
| F♯ major (6 sharps) | V7 | Dominant |
| D♯ minor (6 sharps) | VII7 | Subtonic |
| F♯ minor (harmonic minor, 3 sharps) | V7 | Dominant |
Progressions with C♯ dominant seventh
- Jazz ii–V–I in F♯ major (ii7–V7–Imaj7): G♯m7 – C♯7 – F♯maj7
- 12-bar blues in F♯ major (I7–IV7–V7): F♯7 – B7 – C♯7
- Minor cadence in F♯ minor (i–iv–V7): F♯m – Bm – C♯7
C♯ dominant seventh or D♭ dominant seventh?
C♯ dominant seventh (C♯7) and D♭ dominant seventh (D♭7) are the same chord with two names: they sound the same and use the same frets.
The spelling depends on the key: it is written D♭ dominant seventh in flat keys and C♯ dominant seventh in sharp keys.
Frequently asked questions
What notes are in the C♯ dominant seventh chord?
C♯, E♯, G♯ and B: root, major third, perfect fifth and minor seventh. Its formula is 1-3-5-♭7.
Which keys use C♯ dominant seventh?
Mainly as the V7 in F♯ major and the V7 in F♯ minor. In total it appears in 3 major and minor keys.
Is D♭ dominant seventh the same chord as C♯ dominant seventh?
Yes: D♭ dominant seventh and C♯ dominant seventh sound the same and are played the same way. It is written D♭ dominant seventh in flat keys and C♯ dominant seventh in sharp keys.
What chord does C♯ dominant seventh resolve to?
As a dominant seventh, C♯ dominant seventh (C♯, E♯, G♯ and B) resolves naturally to F♯ major: its third rises a half step to the new tonic and its seventh falls to the third of the next chord.