Intervals
An interval is the distance between two notes. Its number comes from counting letter names, including both ends: C up to E is a 3rd (C, D, E). Its quality (major, minor, perfect) comes from the exact number of half steps.
Intervals above the tonic of a major scale
| Interval | Half steps | In C major |
|---|---|---|
| Major 2nd | 2 | C → D |
| Major 3rd | 4 | C → E |
| Perfect 4th | 5 | C → F |
| Perfect 5th | 7 | C → G |
| Major 6th | 9 | C → A |
| Major 7th | 11 | C → B |
| Octave | 12 | C → C |
Every interval from the tonic up the major scale is either major (2nd, 3rd, 6th, 7th) or perfect (4th, 5th, octave). Make a major interval one half step smaller and it becomes minor: C up to E♭ is a minor 3rd.
The 3rd, 4th, 5th and 6th of every key
The 3rd and 5th build the key’s main chord, and the 4th and 5th are the roots of its other main chords.
| Key | 3rd | 4th | 5th | 6th |
|---|---|---|---|---|
| C major | E | F | G | A |
| G major | B | C | D | E |
| D major | F♯ | G | A | B |
| A major | C♯ | D | E | F♯ |
| E major | G♯ | A | B | C♯ |
| B major | D♯ | E | F♯ | G♯ |
| F♯ major | A♯ | B | C♯ | D♯ |
| C♯ major | E♯ | F♯ | G♯ | A♯ |
| F major | A | B♭ | C | D |
| B♭ major | D | E♭ | F | G |
| E♭ major | G | A♭ | B♭ | C |
| A♭ major | C | D♭ | E♭ | F |
| D♭ major | F | G♭ | A♭ | B♭ |
| G♭ major | B♭ | C♭ | D♭ | E♭ |
| C♭ major | E♭ | F♭ | G♭ | A♭ |
Reading about it is a start. Ten minutes of practice a day makes it automatic.
Practice intervals →