Guitar Chord Families – How Chords Relate to Each Other

Whenever you’re trying to figure out a song by ear, or working on one of your compositions, harmony always plays a big part. 

The chords that exist in a progression directly relate to the melody, they imply a certain function or feeling, and there are explicit reasons as to why some chords sound good or seem to fit in a certain context.

This is where the concept of “chord families” comes in. It can also be called “harmonic field”, and can be often be discerned from reviewing a chord key chart to find what key the song is in.

This KillerGuitarRigs Guide will go in-depth into this matter to teach you the most important aspects you must understand and master to become a more complete musician in general.

In order to fully comprehend every section of the guide, you should be familiarized with some concepts, such as what is a major scale, common chord qualities (major, minor, diminished), relative major/minor keys, and modes.

Chord Families: What Kinds of Chords Exist in a Key, and How Are They Represented?

When we talk about “chord families”, we are implying a group of chords that naturally occur in a given key. The interval between a chord and the key to which it belongs dictates its harmonic function.

Some chords “feel” like home, some of them make you feel like you’re moving away from it, and others create tension that almost asks to be resolved afterward. Knowing which chords sound the way you want can help you compose better songs.

Let’s use the key of C Major to start. Since it has no accidentals (sharps or flats), it is the most commonly used key to demonstrate harmonic concepts.

The C Major scale has the following notes:

• C (Root)
• D (Major Second)
• E (Major Third)
• F (Perfect Fourth)
• G (Perfect Fifth)
• A (Major Sixth)
• B (Major Seventh)

C Major’s chord family contains the following chords:

Notice there are different types of chords – major, minor and diminished. An important feature of chord families is that they follow the same pattern, regardless of the key center.

You should also get used to seeing chords represented by Roman numerals. “I” is the root or key center, “II” is the second degree, and so on.

Minor chords are sometimes represented by lowercase numerals, but if they are represented by uppercase characters, they are still minor.

Harmonic Field and Chord Qualities

The chord family of a Major key always respects this pattern:

• Degrees I, IV and V are Major
• Degrees II, III and VI are minor
• Degree VII is diminished

If you use 7^th chords (4 note chords instead), the pattern is as follows:

• Degrees I and IV are Maj7
• Degrees II, III and VI are min7
• Degree V is dominant/7
• Degree VII is half diminished/m7b5

This is one of the most important naturally occurring patterns to memorize in harmony. 

Knowing how to apply it to any key center means you will automatically know which chords are more likely to be used in a song you’re learning.

For example, if you’re learning a song in the key of C Major, you should immediately realize these are the chords that make the most sense to use:

• C Major / CMaj7
• D minor / Dmin7
• E minor / Emin7
• F Major / FMaj7
• G Major / G7
• A minor / Amin7
• B diminished / Bm7b5

Major Keys Chart

The following chart illustrates which chords belong to the chord family of every major key. Use it for future reference and while practicing figuring out the harmonic field of random keys.

Key	I	ii	iii	IV	V	vi	vii
C Major	C Major	D minor	E minor	F Major	G Major	A minor	B diminished
Db Major	Db Major	Eb minor	F minor	Gb Major	Ab Major	Bb minor	C diminished
D Major	D Major	E minor	F# minor	G Major	A Major	B minor	C# diminished
Eb Major	Eb Major	F minor	G minor	Ab Major	Bb Major	C minor	D diminished
E Major	E Major	F# minor	G# minor	A Major	B Major	C# minor	D# diminished
F Major	F Major	G minor	A minor	Bb Major	C Major	D minor	E diminished
F# Major	F# Major	G# minor	A# minor	B Major	C# Major	D# minor	E# diminished(= F#)
G Major	G Major	A minor	B minor	C Major	D Major	E minor	F# diminished
Ab Major	Ab Major	Bb minor	C minor	Db Major	Eb Major	F minor	G diminished
A Major	A Major	B minor	C# minor	D Major	E Major	F# minor	G# diminished
Bb Major	Bb Major	C minor	D minor	Eb Major	F Major	G minor	A diminished
B Major	B Major	C# minor	D# minor	E Major	F# Major	G# minor	A# diminished

Minor Keys Chart

This chart fulfills the same purpose as the last one, but it represents minor keys instead.

Notice how each key center uses the same set of chords as its relative major key, but is centered on a different tonic (I chord).

Key	i	ii	III	iv	v	VI	VII
A minor	A minor	B diminished	C Major	D minor	E minor	F Major	G Major
Bb minor	Bb minor	C diminished	Db Major	Eb minor	F minor	Gb Major	Ab Major
B minor	B minor	C# diminished	D Major	E minor	F# minor	G Major	A Major
C minor	C minor	D diminished	Eb Major	F minor	G minor	Ab Major	Bb Major
C# minor	C# minor	D# diminished	E Major	F# minor	G# minor	A Major	B Major
D minor	D minor	E diminished	F Major	G minor	A minor	Bb Major	C Major
Eb minor	Eb minor	E# diminished	F# Major	G# minor	A# minor	B Major	C# Major
E minor	E minor	F# diminished	G Major	A minor	B minor	C Major	D Major
F minor	F minor	G diminished	Ab Major	Bb minor	C minor	Db Major	Eb Major
F# minor	F# minor	G# diminished	A Major	B minor	C# minor	D Major	E Major
G minor	G minor	A diminished	Bb Major	C minor	D minor	Eb Major	F Major
G# minor	G# minor	A# diminished	B Major	C# minor	D# minor	E Major	F# Major

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Relative Major and Minor Keys – Overview and How to Apply in a Harmonic Context

The concept of relative keys/scales is simple. Two scales share the same set of notes: one is major, the other is minor, and their root note is different.

Every major scale/key has a relative minor, and vice-versa.

You can find the relative minor of a major key by moving up a major sixth or down a major third.

For instance, C Major is the relative major scale of A minor (A is a major sixth away from C).

C Major is made up of the following notes: C, D, E, F, G, A, B.

A minor on the other hand looks like this: A, B, C, D, E, F, G.

Being able to quickly identify relative scales and keys will allow you to locate yourself much better when playing patterns on the guitar (Read our full guide to scales here).

The following table shows you the relative major and minor scales you should know.

Major Key	Relative Minor Key
C Major	A minor
D Major	B minor
E Major	C# minor
F Major	D minor
G Major	E minor
A Major	F# minor
B Major	G# minor
Db Major	Bb minor
Eb Major	C minor
Gb Major	Eb minor
Ab Major	F minor
Bb Major	G minor

This relationship is often represented on the Circle of Fifths, an essential tool to understand how key centers work.

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What’s the Function of Each Chord in a Key?

The chords of a given harmonic field can be grouped according to their “harmonic function”. This is a category that tells us what kind of role that chord has in that tonality.

For this example, we will use the key of C Major, and 7^th chords instead of triads. We have 3 different types of harmonic functions:

• Tonic Chords
• Subdominant Chords
• Dominant Chords

Tonic chords sound like “home”. They establish a sense of root and tonality in a song, which is why songs frequently start or finish songs. The chord family of any key has the following tonic degrees:

• I 
• iii 
• vi 

None of these chords will have the 4^th degree of the scale (in C Major, the 4^th degree is F).

Subdominant chords are used to transmit a sensation of moving away from the key center’s feeling of “home”. These are frequently used to help create tension (used before a dominant chord). The following chord degrees are subdominant:

• ii 
• IV 

In contrast to the tonic chords, these contain the 4^th degree of the scale.

Dominant chords are used to create tension in music. They sound unstable, quite unlike tonic chords, and they almost literally “ask” to be resolved. These are the dominant degrees:

• V 
• vii 

The main particularity about these chords is the fact that they have a tritone interval (diminished fifth) in them. 

Harmonic Functions in Common Chord Progressions

Let’s put this into practice by looking at some of the most common cadences in western music. There are countless songs that feature these chord progressions – sometimes they make up the entire song.

You’ll notice in many cases, dominant chords move toward tonic chords, and subdominant move toward dominant chords. However this isn’t a rule, and you can mix and match every chord any way you see fit.

Cadence	Harmonic Functions
ii – V – I	Subdominant – Dominant – Tonic
I – vi – ii – V	Tonic – Tonic – Subdominant – Dominant
I – IV – V	Tonic – Subdominant – Dominant
I – V – vi – IV	Tonic – Dominant – Tonic – Subdominant
I – IV – VI – V	Tonic – Subdominant – Tonic – Dominant

Being able to quickly identify the function of each chord in a key can help you be more creative by being aware of potential chord substitutions and having a better sense of how music generally works.

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The Concept of Chord Families Applied to the Modes

We can apply the same concept to the modes of the major scale and obtain even more chord families.

If you’re already familiarized with how modes work, you just need to reapply the same logic to chord degrees instead of the notes of a scale.

Let’s look into a few practical examples to make this clearer. 

For the purpose of demonstrating this concept, we will use the chord families that come from the modes of the C Major scale (C Ionian, D Dorian, E Phrygian, F Lydian, G Mixolydian, A Aeolian and B Locrian).

Ionian

The Ionian mode is the same as the major scale, so there isn’t much more to be said about it other than what’s explained in the previous sections. 

The C Major chord family looks like this on the staff:

Dorian

The Dorian mode has the following formula: 1, 2, b3, 4, 5, 6, b7

Dorian chord families follow the structure shown below:

• i – Minor 7
• ii – Minor 7 
• bIII – Major 7 
• IV – Dominant 7
• v – Minor 7 
• vi – Half Diminished
• bVI – Major 7 

Here is the corresponding chord family if we are in the key of D Dorian:

Phrygian

Phrygian can be represented by the following formula: 1, b2, b3, 4, 5, b6, b7.

A Phrygian chord family will look like this:

• i
• bII
• bIII
• iv
• v
• bVI
• bvii

In the key of E Phrygian, this is the harmonic field on the staff:

Lydian

The Lydian mode follows this formula: 1, 2, 3, #4, 5, 6, 7.

The corresponding chord families follow this structure:

• I
• II
• iii
• #iv
• V
• vi
• vii

Here are the chords of the F Lydian family written on a staff:

Mixolydian

The Mixolydian mode can be represented by the following formula: 1, 2, 3, 4, 5, 6, b7.

Its chord families all follow this pattern:

• I
• ii
• iii
• IV
• v
• vi
• bVII

Here’s what this chord family looks like in G Mixolydian:

Aeolian

As you probably already know, the Aeolian mode corresponds to the natural minor scale. The corresponding formula is: 1, 2, b3, 4, 5, b6, b7.

Its chord family has the following structure:

• i
• ii
• bIII
• iv
• v
• bVI
• bVII

Here are the chords that belong to the family of A Aeolian:

Locrian

Lastly, the Locrian mode follows this formula: 1, b2, b3, 4, b5, b6, b7.

Locrian chord families follow the pattern below:

• i
• bII
• biii
• iv
• bV
• bVI
• bvii

Here is how you would write the B Locrian chord family on a staff:

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Final Thoughts about Guitar Chord Families

As a guitarist and musician in general, it pays off big time to be familiarized with every key’s chord family, or harmonic field. Once you’re past beginner chords (whether learning yourself or learning online), chord families should be your first step into learning theory.

Knowing which chords exist in each key and the function they serve is crucial to writing songs that make sense and express the feelings you want to convey through the song’s harmony.