What Are the Primary Chords in a key of Music?

It all starts with something called tonality

Tonality is a sequence of notes (aka tones) in a key of music in which each tone has a specific function within the key.

Even though there are 12 notes in music...

...any given key of music has 7 notes such as the key of C Major.

Without the emphasis of a key of music, any given tone in music is simply random because there is no tonal center to reference it.

In other words, a C is simply a random note without any reference as to what key it is being played in.But if it's in the context of the key of C Major, it serves as the tonal center of that key. It's actually referred to as the tonic in the key of C Major. The tonic is the note that all other tones gravitate to in the key. Think of it as home base. No matter what the tones are in a song, it always wants to resolve to the tonic in the end.

In fact, each one of the 7 tones in a Major key of music has a specific name and function.

Note Names of the Diatonic Scale

In another article, I talked about the power of the number system and how each tone gets it's name. You can read about them here.

Each degree of the scale (or note) in a Major key has a corresponding chord

Since there are 7 notes in a Major key of music, there are 7 chords associated with them. This is also known as diatonic harmony. They are a combination of Major and minor triads with one of them being a diminished triad.

1 Chord C Major

2 Chord D minor3 Chord E minor4 Chord F Major5 Chord G Major6 Chord A minor7 Chord B diminished (the degree symbol denotes it as a diminished chord)

You can see in the following table at a glance what chords fall into Major, minor and diminished categories. These are referred to as chord qualities.

Diatonic Harmony in Major Keys

Now that we have all 7 chords in a Major key represented, what are the primary chords in all 12 Major keys?

Note: Upper case roman numerals are used to denote the one, four and five chords respectively.  I will also progress around the circle of 5ths in counter clockwise order.  If you're not familiar with the Circle of 5ths, here is an article on the Circle of 5ths that will help you understand it visually.

The Primary chords in all 12 Major keys

Key of C Major

I C Major Triad

IV F Major Triad

V Major Triad

Key of F Major

I F Major Triad

IV B Flat Major Triad

V C Major Triad

Key of B Flat Major

I B Flat Major Triad

IV E flat Major Triad

V F Major Triad

Key of E Flat Major

I E flat Major Triad

IV A flat Major Triad

V B flat Major Triad

Key of A Flat Major

I A flat Major Triad

IV D flat Major Triad

V E flat Major Triad

Key of D Flat Major

I D flat Major Triad

IV G flat Major Triad

V A flat Major Triad

Key of G Flat Major

I G flat Major Triad

IV C flat Major Triad

V D flat Major Triad

Key of B Major

I B Major Triad

IV E Major Triad

V F sharp Major Triad

Key of E Major

I E Major Triad

IV A Major Triad

V B Major Triad

Key of A Major

I A Major Triad

IV D Major Triad

V E Major Triad

Key of D Major

I D Major Triad

IV G Major Triad

V A Major Triad

Key of G Major

I G Major TriadIV C Major Triad

V D Major Triad

Primary chords in all 12 minor keys

The key of A minor is the relative minor key of C Major. This essentially means that they share the same exact tones but are in a different number sequence.In the case of the A minor key, A is the tonic. This makes A the tonal center (or tonic) of the key.The  7 notes in a minor key of music have 7 corresponding chords associated with them. They are a combination of Major and minor triads with one of them being a diminished triad.

i A minor Triadii B diminished Triad

III C Major Triad

iv D minor Triad

v E minor Triad

VI F Major Triad

VII G Major Triad

The following table shows what chords fall into Major, minor and diminished categories in a minor key. These are chord qualities in minor keys.

Diatonic Harmony in minor Keys

Just as with Major keys of music, minor keys have their primary chords as well and are constructed upon the first, fourth and fifth tones.

The Primary Chords in Natural Minor keys

Note: Lower case roman numerals are used to denote the one, four and five chords respectively.

Key of A Minor

i A minor Triad

iv D minor Triad

v E minor Triad

Key of D Minor

i D minor Triad

iv G minor Triad

v A minor Triad

Key of G Minor

i G minor Triad

iv C minor Triad

v D minor Triad

Key of C Minor

i C minor Triad

iv F minor Triad

v G minor Triad

Key of F Minor

i F minor Triad

iv B flat minor Triad

v C minor Triad

Key of B flat Minor

i B flat minor Triad

iv E flat minor Triad

v F minor Triad

Key of E flat Minor

i E flat minor Triad

iv A flat minor Triad

v B flat minor Triad

Key of A flat Minor

i A flat minor Triad

iv D flat minor Triad

v E flat minor Triad

Key of D flat Minor

i D flat minor Triad

iv G flat minor Triad

v A flat minor Triad

Key of G flat Minor

i G flat minor Triad

iv C flat minor Triad

v D flat minor Triad

Key of B Minor

i B minor Triad

iv E minor Triad

v F Sharp minor Triad

Key of E Minor

i E minor Triad

iv A minor Triad

v B minor Triad