C7 C dominant seventh chord
- Notes
- C E G Bb
- Formula
- 1 3 5 b7
- Semitones
- 0 4 7 10 above the root
- Other symbols
- Cdom7
C to E is a major third (4 semitones), E to G is a minor third (3 semitones), G to Bb is a minor third (3 semitones). A dominant seventh is a major triad plus a minor seventh (Bb, 10 semitones above C). It is the V chord that leads back home, and the basic chord of the blues.
C7 on the piano
Root position from C4: C4, E4, G4, Bb4. Middle C is C4.
C7 on the guitar
Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has C as its lowest note.
x 3 2 3 1 0 (low E to high e)
Sounds C3 E3 Bb3 C4 E4, fifth left out
x 3 5 3 5 3 (low E to high e)
Sounds C3 G3 Bb3 E4 G4
8 10 8 9 8 8 (low E to high e)
Sounds C3 G3 Bb3 E4 G4 C5
The barre shapes are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play dominant seventh chords on other roots.
Inversions of C7
An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.
| Position | Notes, bass first | Named | Listen |
|---|---|---|---|
| Root position | C E G Bb | C7 | |
| 1st inversion | E G Bb C | C7/E | |
| 2nd inversion | G Bb C E | C7/G | |
| 3rd inversion | Bb C E G | C7/Bb |
Where C7 fits
C7 is V7 in F major, V7 in F minor. Its E and Bb are a tritone apart (6 semitones). In F major the E usually rises a half step to F and the Bb falls a half step, which is why C7 pulls so strongly towards F.