Primary Chords in Major and Minor Keys

Question: What are the primary chords in any key and how many are there?

Answer:

Major Keys
First, there are 3 primary chords in each key. They are built off of the 1 st , 4 th and 5 th scale degrees. For instance, in C Major, the 1 is C.the 4 is F.the 5 is G. Simply put the word "Major" after each of these 3 scale tones and you come up with the 3 primary chords of the key, C Major, F Major and G Major.

Another quick example:

G Major Scale -
The 1 st degree of the scale is G, so that's the first chord - G Major.
The 4 th degree of the scale is C, so that's the second chord - C Major.
The 5 th degree of the scale is D, so that's the third chord - D Major.]

Therefore, the primary chords in G Major, are G Major, C Major and D Major.

Minor Keys

These primary chords in minor are also built on 1, 4 and 5, although they are not all "major" chords. It depends on the type of minor that you are playing (natural minor, harmonic minor, or melodic minor).

In the natural minor, the 1 chord is Minor, the 4 Chord is Minor and the 5 Chord is also Minor.
In harmonic, the 1 chord is Minor, the 4 Chord is Minor and the 5 Chord is Major.

Melodic Minor is a little tricky, because it depends on if the melody is ascending, or decending.
In either case, the 1 chord is minor, the 4 chord is major (going up) and minor (going down) and the 5 chord is major (going up) and minor (going down).