Chords and scales are the same notes, laid out differently
A chord plays notes together; a scale plays the same material one at a time. If a tune is over Dm7, the notes D F A C are the chord, and the scale that holds them plus the others that sound good (E, G, B) is D Dorian. Pick melody notes from that scale and they will fit the chord. That is chord-scale theory.
The cheat sheet (on C)
| Chord | Chord notes | Scale | Scale notes |
|---|---|---|---|
| Cmaj7 (major 7th) | C E G B | Major | C D E F G A B |
| Cm7 (minor 7th) | C E♭ G B♭ | Dorian | C D E♭ F G A B♭ |
| C7 (dominant 7th) | C E G B♭ | Mixolydian | C D E F G A B♭ |
| Cø7 (half-diminished) | C E♭ G♭ B♭ | Locrian | C D♭ E♭ F G♭ A♭ B♭ |
| Cm (minor) | C E♭ G | Natural Minor | C D E♭ F G A♭ B♭ |
| Cm(maj7) (minor-major 7th) | C E♭ G B | Melodic Minor | C D E♭ F G A B |
| Cmaj7♯11 (major 7 sharp 11) | C E G B F♯ | Lydian | C D E F♯ G A B |
| C7♯11 (dominant 7 sharp 11) | C E G B♭ F♯ | Lydian Dominant | C D E F♯ G A B♭ |
| C7alt (altered dominant) | C E B♭ D♯ A♭ | Altered | C D♭ E♭ F♭ G♭ A♭ B♭ |
| C7♯5 (augmented 7th) | C E G♯ B♭ | Whole Tone | C D E F♯ G♯ B♭ |
| Cm11 (minor 11th) | C E♭ G B♭ D F | Dorian | C D E♭ F G A B♭ |
| C13 (dominant 13th) | C E G B♭ D A | Mixolydian | C D E F G A B♭ |
The four chords of the major scale
Build a seventh chord on each degree of the major scale and you get maj7, m7, m7, maj7, 7, m7, m7♭5. Each one fits the same major scale, started on its own root: Ionian (I, IV is Lydian), Dorian (ii), Phrygian (iii), Mixolydian (V), Aeolian (vi), Locrian (vii). Learn the modes by the chord they sit over, not by their order.
Avoid notes
Each scale has a note or two that clash with the chord when held. The classic example: the natural 4th over a major 7th chord clashes with the 3rd, which is why jazz players choose Lydian (♯4) over a tonic chord. Passing through is fine; landing on it is not.
How to practise
- Warm-up: maj7, m7, 7 and m7♭5.
- Working set: adds minor-major 7, ♯11 chords.
- Heavy lift: altered, whole tone and extended chords.
See every scale on its scale page (including lydian dominant and altered), the chords in altered chords, and the Chord-Scale program.
Frequently asked questions
What is chord-scale theory?
The idea that every chord has a scale that contains its notes plus the extra notes (9th, 11th, 13th) that sound good over it. Improvisers use the chord's scale to choose melody notes.
Which scale do I play over a minor 7th chord?
Dorian is the standard choice: the natural minor scale with a raised 6th. If the chord is the ii chord of a major key, Dorian is simply that key's scale starting on the 2nd note.
Which scale do I play over a dominant 7th chord?
Mixolydian for a plain 7th chord. For 7♯11 use Lydian dominant, and for 7alt or 7♭9♯9 use the altered scale. Dominant chords have the most choices because they can carry the most tension.
Why does the scale depend on the chord and not just the key?
Because the notes change with the chord's role. In C major, Dm7 uses Dorian, G7 uses Mixolydian and Cmaj7 uses Ionian: all the same seven notes, but starting on a different root, so a different note gets the emphasis.
Do I need to learn every mode?
Start with the four from the major scale: Ionian over maj7, Dorian over m7, Mixolydian over 7, Locrian over m7♭5. Then add melodic minor, Lydian and its dominant, and altered.