Explore chords · Bass
C 7th chord on bass (C7)
Also called or written C7, C, C Dominant 7th or C Major Minor 7th
C 7th is built from C, E, G, and B♭. The 8th-fret shape stretches the pinky to fret 10 on the A string, making clean fretting the main challenge.
How it is built
Formula 1, 3, 5, ♭7
How do you play a C 7th chord on bass?
C 7th is played at the 8th fret as 8 10 8 9: index finger on the E string at fret 8, pinky finger on the A string at fret 10, middle finger on the D string at fret 8 and ring finger on the G string at fret 9.
Full note and interval breakdown
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 8 | 1 | C (1) |
| 3 (A) | 10 | 4 | G (5) |
| 2 (D) | 8 | 2 | B♭ (♭7) |
| 1 (G) | 9 | 3 | E (3) |
AdvancedThe pinky must reach from the 8th fret to the 10th fret on the A string while the other fingers hold their frets cleanly.
C7/G inversion · fret 2
C 7th is played at the 2nd fret as 3 3 2 3: middle finger on the E string at fret 3, ring finger on the A string at fret 3, index finger on the D string at fret 2 and pinky finger on the G string at fret 3.
Full note and interval breakdown
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 3 | 2 | G (5) |
| 3 (A) | 3 | 3 | C (1) |
| 2 (D) | 2 | 1 | E (3) |
| 1 (G) | 3 | 4 | B♭ (♭7) |
C7/G inversion · fret 14
C 7th is played at the 14th fret as 15 15 14 15: middle finger on the E string at fret 15, ring finger on the A string at fret 15, index finger on the D string at fret 14 and pinky finger on the G string at fret 15.
Full note and interval breakdown
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 15 | 2 | G (5) |
| 3 (A) | 15 | 3 | C (1) |
| 2 (D) | 14 | 1 | E (3) |
| 1 (G) | 15 | 4 | B♭ (♭7) |
C7/B♭ inversion
C 7th is played at the 5th fret as 6 7 5 5: ring finger on the E string at fret 6, pinky finger on the A string at fret 7, index finger on the D string at fret 5 and middle finger on the G string at fret 5.
Full note and interval breakdown
| String | Fret | Finger | Note |
|---|---|---|---|
| 4 (E) | 6 | 3 | B♭ (♭7) |
| 3 (A) | 7 | 4 | E (3) |
| 2 (D) | 5 | 1 | G (5) |
| 1 (G) | 5 | 2 | C (1) |
Why it sounds like that
C 7th uses the formula 1, 3, 5, ♭7. The minor 7th interval between C and B♭ gives the chord its dominant quality, and the diminished 5th between E and B♭ adds tension. Compare it with C major, which omits the ♭7.
What goes wrong with C 7th?
- Letting the pinky collapse and buzz the A string at fret 10.
- Allowing the ring finger to touch the D string and mute it.
- Striking the open E string instead of fretting it at the 8th fret.
When to use it
C 7th is the V chord in F major, so it appears in progressions like F–B♭–C–F (I–IV–V–I). Its dominant pull suits blues, jazz, and rock bass lines that resolve to F.
Changing to and from C 7th
- Move to F major by lifting the pinky and shifting the index and middle fingers down one string each.
- Slide the shape down two frets to the 6th fret to play B♭ 7th.
Which voicing to use
The 8th-fret shape has C in the bass and is the most direct voicing. The C7/G inversion at the 3rd fret puts G in the bass for a smoother transition from F major, while the C7/B♭ inversion at the 6th fret leads into F major by step.
Other C chords
Common questions
How does C 7th differ from C major?
C 7th adds a B♭ note, the minor 7th, to the C major triad. That B♭ creates a tritone with E, giving C 7th its dominant tension.
Why is C 7th called a dominant 7th chord?
C 7th is built on the fifth degree of F major, where it functions as the dominant. The name comes from that dominant function, not from the chord's internal intervals.
Can C 7th be played with a barre?
The 8th-fret shape uses individual fingers, not a barre. The C7/G inversion at the 3rd fret also uses separate fingers, so no barre is required.