Learning what the circle of fifths is and how to use it, can help you to memorize the number of flats or sharps in a key. It can also be of assistance when you want to compose chord progressions. I strongly recommend before you continue reading, that you do a Google image search for Circle Of Fifths, the visual aid will be very helpful during this lesson.

The key of C major has no sharps or flats, this is the most commonly used key signature when composing songs and writing music lessons, because its the easiest to remember.

Notice how, as you move right and left around the circle, you see the other major and minor keys, the number of sharps or flats in each, and which note is the root.

There are a couple of basic rules that go along with the circle of fifths which we can follow to help us remember key names, and the number of flats and sharps. These are referred to the order of sharps and flats.

Order of sharps=

F-C-G-D-A-E-B

Order of flats=

B-E-A-D-G-C-F

Notice that the order of flats is the inverse of the order of sharps.

Each of these, shows the order in which you add flats or sharps to a key when attempting to change it.

For instance, in the key of C major, there are no sharps or flats, but when you add a sharp F, it becomes the key of G major, add a sharp C to that, and it becomes D major.

This holds true for the flats, add a flat B to C major and you have the key of F major, add a flat E as well and you get B flat major.

With that said lets move to the right, around the wheel.

C major, no sharps or flats
G major, 1 sharp, (F)
D major, 2 sharps, (F-C)
A major, 3 sharps, (F-C-G)
E major, 4 sharps, (F-C-G-D)
B major, 5 sharps, (F-C-G-D-A)
F# major, 6 sharps, (F-C-G-D-A-E)
C# major, 7 sharps, (F-C-G-D-A-E-B)

Do you see the correlation between the circle of fifths and the order of sharps here?

Also, notice how the last sharp you add is just one letter behind the root note. So if you are in the key of A, you know the last sharp you are going to add is G, then you can look at the order of sharps and say, ok F, C and G are the the sharps in the key of A.

Now lets start over at C major and move to the left.

C major, no flats or sharps
F major, 1 flat, (B)
Bb major, 2 flats, (B-E)
Eb major, 3 flats, (B-E-A)
Ab major, 4 flats, (B-E-A-D)
Db major, 5 flats, (B-E-A-D-G)
Gb major, 6 flats, (B-E-A-D-G-C)
Cb major, 7 flats, (B-E-A-D-G-C-F)

Do you see the correlation between the circle of fifths and the order of flats here?

You may notice that the root note is always the second to last flat in each key. So from this you can conclude that if the last flat in the key is D, you can look at your order of flats and see B-E-A-D then move back one spot D-A, and that is the key you are playing in.

So how does all of this help you to write a chord progression?

Well the answer is in the name, circle of fifths. This is literally a circle with which each movement clockwise is a fifth interval up, or a fourth interval down. For instance:

G is a perfect fifth above C, (C-D-E-F-G)
G is also a perfect fourth below C, (G-A-B-C)

So playing a C chord to a G chord, is the same as playing a I chord to a V chord, and playing a G chord to a C chord is the same as playing a I chord to a IV chord.

So what makes this so convenient?

These intervals are called perfect because they resolve completely. Thus when you play these chords in succession of each other, you will have complete resolution throughout your progression.

To be a little more clear, I will write out a chord progression below for you to play.

|--x----3----x----5----x----x-----------|
|--5----3----6----5----8----x----10----|
|--5----4----7----5----9----7----10----|
|--5----5----7----7----9----6----10----|
|--3----5----5----7----7----5----8-----|
|--x----3----x----5----x----7-----------|

How did I get this progression?

By combining the concepts of circle of fifths progression and diatonic harmony.

I used the key of C major, and diatonic harmony in the key of C major is:

1 = C major
2 = D minor
3 = E minor
4 = F major
5 = G major
6 = A minor
7 = B dim

I then applied these qualities* to my circle of fifths chord progression and got:

1 = C major
2 = G major
3 = D minor
4 = A minor
5 = E minor
6 = B dim
7 = F major

This should have plenty of tension and resolution which is what makes a chord progression sound musical, but also notice how well each chord moves to the next, the transitions are very smooth, which is why circle of fifths chord progressions are so commonly used.

*quality defines whether a chord or interval is major, minor, perfect, augmented, or diminished

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