Major Diatonic Chords I, ii, iii, and IV

In the next two lessons we will learn to play all seven diatonic chords of the major scale in a single four-fret position. You won't shift your fretting hand at all.

In this first lesson of the two, we will learn the position and the first four chords: I, ii, iii, and IV.

Seventh Chords and Triads

We are going to learn each chord as a seventh chord. This means each chord will have a Root, 3rd, 5th, and 7th.

In a lot of situations and styles, you'll only need or apply the triad—Root, 3rd, and 5th. I've found it's easier to teach students the 7th chords and ask them to drop the seventh to get the triad, instead of learning everything twice!

Extending the Major Scale

You could play the diatonic chords up and down the neck hunting for chord shapes you already know. If you do that, you'll be shifting all over the place. That's inefficient and not how you often play.

Instead, we will learn to play all seven diatonic chords in one spot without any shifting. For this, we will take the one-octave major scale shape you've learned and extend it by three notes above and one note below.

All examples are in the key of G major: G, A, B, C, D, E, and F#. But remember, this is the same for all keys.

In the diagram below, do you see the one-octave G major scale shape you know from G to G? We can extend it with the notes A, B and C in the next higher octave. These are the same as the 2nd, 3rd, and 4th, but an octave higher. Then, we add an F# below the low G. From the scale shape you know, this is just the 7th an octave lower.

Play the notes of the whole shape starting on F# on the E-string using your first finger. Using one finger per fret, play through to the highest note C and back down. These are all of the notes of G major in the four frets under your fingers.

It will sound funny to you starting and ending on the F# because your ear wants to hear the resolution on G. Go ahead and play the G at the end if it makes you feel better.

You need to memorize this shape for the major scale. We will play all of the diatonic chords using only these notes.

Visualize the Major Scale

Important! You want to visualize this shape underneath the diatonic chord shapes as you play them. You'll see I've ghosted in the notes of the shape on the diagrams to help you visualize the relationship.

Ready? Here we go...

The I Chord

The I chord (say: "the one chord") starts on the first degree of the key.

The I chord is always a major 7th chord. Or, when you leave off the 7th, a major triad.

Example: G is the first degree of the G scale. The I chord in the key of G is Gmaj7 or G.

Be strict with the one-finger-per-fret fingering for all of these chord shapes.

The ii Chord

The ii chord ("the two chord") starts on the second degree of the key.

The ii chord is always a minor 7th chord. Or, leaving off the 7th, you have a minor triad.

Example: A is the second note of the G scale. The ii chord in the key of G is Am7 or Am.

You will notice this is a different shape from the minor 7th chord shape you first learned. This new fingering lets you stay in a single position without shifting. If you play the minor 7th fingering you know, you'll see and hear they are the same 4 notes: A, C, E and G. Try it.

The iii Chord

The iii chord ("the three chord") starts on the third degree of the key.

The iii chord is always a minor 7th chord, or a minor triad.

Example: B is the third note of the G scale. The iii chord in the key of G is Bm7 or Bm.

This fingering, starting on your first finger, should look familiar to you.

The IV Chord

The IV chord ("the four chord") starts on the fourth degree of the major scale.

The IV chord is always a major 7th chord, or a major triad.

Example: C is the fourth note of the G scale. The IV chord in the key of G is Cmaj7 or C.

Wait, I Thought Chords I and IV Had Flat Sevens!

If this came to mind, you are being an observant student, and you've been working on your blues.

Traditional harmony sticks to the notes of the key. It's the blues which breaks the “rules”. A key part of the blues sound is the flatted 7ths added to the I and IV chords. The flat sevens are bending the rules and are what make the blues sound different from, say, Mozart.

We will explore this distinction more later. Learn the I and IV chords as major 7ths here!

Summary of I, ii, iii, and IV

Memorize the fingerings, and remember the chord qualities for each chord:

I & IV are major 7ths or major triads.

ii & iii are minor 7ths or minor triads.

Do the Exercises

Study the exercises to get the comfortable with this major scale position and the first four chords.

In the next lesson you'll learn the last three diatonic chords: V, vi and vii. Then, we'll go on to the good part—applying the diatonic chords!