Theory · glossary
Seventh chord
Also called 7th chord, dominant 7th, maj7, major seventh, m7, minor seventh
A seventh chord is a triad plus a fourth note a seventh above the root. The three you meet most are the major seventh (Cmaj7: C E G B), the dominant seventh (C7: C E G Bb) and the minor seventh (Cm7: C Eb G Bb).
A seventh chord adds one note to a triad: stack one more third on top, and it lands on the seventh note of the scale, counting the root as one. In C that note is B or Bb. The type depends on the triad underneath and on how far the seventh sits above the root: 11 semitones for a major seventh, 10 for a minor seventh.
| Type | Symbol | Notes | Sound |
|---|---|---|---|
| Major seventh | Cmaj7 | C E G B | soft, dreamy |
| Dominant seventh | C7 | C E G Bb | bluesy, restless |
| Minor seventh | Cm7 | C Eb G Bb | mellow, smooth |
| Half-diminished | Cm7b5 | C Eb Gb Bb | dark, unsettled |
Two rarer types fill out the family. The diminished seventh stacks three minor thirds, so its seventh is only 9 semitones up: G#dim7 (G# B D F) comes from A harmonic minor and sounds like a silent-film cliffhanger. The minor-major seventh, Cm(maj7) (C Eb G B), puts a major seventh on a minor triad for a tense, spy-movie sound.
A bare 7 always means the dominant type. C7 has Bb; Cmaj7 has B natural. Mixing the two up is an easy mistake, and maj7 vs 7 chords compares them side by side.
In C major, the diatonic sevenths are Cmaj7, Dm7, Em7, Fmaj7, G7, Am7 and Bm7b5. The key has one dominant seventh, G7 (G B D F), and its B and F pull toward C and E, which is why G7 to C sounds so final. The chords in C major page lists all seven.
Seventh chords run through jazz, soul and R&B, and folk and blues chord sheets use plain dominant sevenths such as G7 and E7. The online chord player plays every key as triads or 7ths. Gelato Chord has the same triads-or-7ths choice, and Gelato Synth’s chord-type row has a 7th setting that switches every pad at once.
Updated . All terms · Try the online chord pads