Interval reference
Major sixth
6 letter names · 9 semitones · C → A
A major sixth spans 6 letter names and 9 semitones. Both halves of that description matter: the number comes from the letters, the quality from the exact size.
Starting on C, a major sixth reaches A. Its shorthand is M6, and traditionally it counts as imperfect consonance.
How big it is
Hear it from any note
The explorer starts on C up to A. Play it one note after the other and then both together — the two ways a major sixth turns up in music — then change the bottom note: the distance stays the same while the spelling follows the letters.
Turned upside down
Move the lower note up an octave and a major sixth becomes a minor third. 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 inversion of a minor third (C up to A)
- The root to the added sixth of a 6 chord (C up to A in C6)
From every starting note
| From | Up a major sixth |
|---|---|
| C | A |
| C♯ | A♯ |
| D | B |
| D♯ | B♯ |
| E | C♯ |
| F | D |
| F♯ | D♯ |
| G | E |
| G♯ | E♯ |
| A | F♯ |
| A♯ | F𝄪 |
| B | G♯ |