Interval reference
Major seventh
7 letter names · 11 semitones · C → B
A major seventh spans 7 letter names and 11 semitones. Both halves of that description matter: the number comes from the letters, the quality from the exact size.
Starting on C, a major seventh reaches B. Its shorthand is M7, and traditionally it counts as dissonance.
How big it is
Turned upside down
Move the lower note up an octave and a major seventh becomes a minor second. The two numbers add up to nine, and the quality flips — major with minor, augmented with diminished, while perfect stays perfect.
Where you meet it
- The seventh of a major seventh chord
- The leading tone below the tonic, inverted
From every starting note
| From | Up a major seventh |
|---|---|
| C | B |
| C♯ | B♯ |
| D | C♯ |
| D♯ | C𝄪 |
| E | D♯ |
| F | E |
| F♯ | E♯ |
| G | F♯ |
| G♯ | F𝄪 |
| A | G♯ |
| A♯ | G𝄪 |
| B | A♯ |