Also written C♯7, C♯ or C♯ Dominant 7th
C♯ 7th is built from C♯, E♯, G♯, and B. The default voicing uses a barre at the first fret and a pinky stretch to the second fret.
The same three notes, with a different one in the bass.
C♯ 7th uses the formula 1, 3, 5, ♭7. The minor 7th interval from C♯ to B gives the chord its dominant quality. Compare it to C♯ major, which lacks the ♭7.
C♯ 7th is the V chord in F♯ major, resolving to F♯ major in progressions like I–IV–V–I (F♯–B–C♯–F♯). Use it in blues, funk, and jazz for a strong dominant sound. It also leads to F♯ major.
The default 1st fret voicing has C♯ in the bass and is compact. The C♯7/E♯ inversion at fret 4 puts E♯ in the bass for a brighter sound. The C♯7/B inversion at fret 10 has B in the bass and is useful for voice leading.
C♯ 7th is played at the 1st fret as 1 1 1 2: barre your index finger across fret 1 and pinky finger on the A string at fret 2.
Tip — The index barre must hold all four strings at fret 1 while the pinky reaches fret 2 on the A string.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | 1 | 1 (barre) | G♯ (5) |
| 3 (C) | 1 | 1 (barre) | C♯ (1) |
| 2 (E) | 1 | 1 (barre) | E♯ (3) |
| 1 (A) | 2 | 4 | B (♭7) |
C♯ 7th is played at the 4th fret as 4 5 4 4: index finger on the G string at fret 4, pinky finger on the C string at fret 5, middle finger on the E string at fret 4 and ring finger on the A string at fret 4.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | 4 | 1 | B (♭7) |
| 3 (C) | 5 | 4 | E♯ (3) |
| 2 (E) | 4 | 2 | G♯ (5) |
| 1 (A) | 4 | 3 | C♯ (1) |
C♯ 7th is played at the 6th fret as 6 8 7 8: index finger on the G string at fret 6, ring finger on the C string at fret 8, middle finger on the E string at fret 7 and pinky finger on the A string at fret 8.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | 6 | 1 | C♯ (1) |
| 3 (C) | 8 | 3 | G♯ (5) |
| 2 (E) | 7 | 2 | B (♭7) |
| 1 (A) | 8 | 4 | E♯ (3) |
C♯ 7th is played at the 9th fret as 10 11 9 11: middle finger on the G string at fret 10, ring finger on the C string at fret 11, index finger on the E string at fret 9 and pinky finger on the A string at fret 11.
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (G) | 10 | 2 | E♯ (3) |
| 3 (C) | 11 | 3 | B (♭7) |
| 2 (E) | 9 | 1 | C♯ (1) |
| 1 (A) | 11 | 4 | G♯ (5) |
C♯ 7th is written as C♯7, or as C#7 in ASCII. It is also called Dominant 7th or Major Minor 7th. It is also spelled D♭ in enharmonic notation for the same sounding root.
C♯ major contains C♯, E♯, and G♯. C♯ 7th adds B, the minor 7th, which creates a tritone with E♯ and gives the chord its dominant pull.
The barre at the first fret requires even pressure across all strings, and the pinky must stretch to the second fret without muting adjacent strings.
The default voicing uses a barre, but you can play the C♯7/E♯ inversion at fret 4 with individual fingers if you prefer.