Circle of Fifths

The Circle of Fifths is an ingenious device for making sense of music.

Cath McCourt’s overview describes the structure of the Circle of Fifths, and outlines how ukulele players might use the diagram.

Relationship between major and minor keys01_Cof5ths_withkeysig

Learning to read the Circle of Fifths helps you to understand the relationship between the major keys and their relative minor keys. A major key and its relative minor use the same key signature, which means their scales include the same sharps (#) and flats (b).

Structure of the Circle of Fifths

Looking at the Circle of Fifths, you’ll see that the major keys are in the outer circle. Beside each major key, in the inner circle, is its relative minor key.

A Minor is the relative minor key for C Major. B Minor is the relative minor key for D Major. F Minor is the relative minor key for Ab Major.


Keryn Henderson 2020

Why call it the Circle of Fifths?

It’s called a ‘circle of fifths’, because moving clockwise around the circle from the 12 o’clock position, the next chord in the circle is the fifth note in the scale.

The fifth note in the:

  • C Major scale is G.
  • G Major scale is D.
  • D Major scale is A.

And so on …

What is a scale?

The Circle of Fifths is based on musical scales. A scale is a sequence of eight notes (an octave).

Look at the C major octave on the piano keys (below). If we play all the white and black keys as we move up the keyboard, we move in semitones (half steps) from key to key. But if we skip a key, we have moved a tone (full step).


Keryn Henderson 2020

Semitones and tones

When we move from C to C#, the keys are a semitone apart.

However moving from C to D, skipping C#, the keys are a tone apart.

There are no black sharp or flat keys between the white E and F keys and the white B and C keys. So, the notes E and F are a semitone apart. Similarly, the notes B and C are also a semitone apart.

To find the notes of a scale, follow the pattern tone, tone, semitone, tone, tone, tone, semitone, tone. (T-T-S-T-T-T-S-T)

This pattern for finding scales on the keyboard also applies to each string on the ukulele fretboard.


The fretboard diagram (below) shows the location of notes on a ukulele fretboard with standard G-C-E-A tuning for soprano, concert and tenor ukes.


Using the Circle of Fifths

The layout of the Circle of Fifths is useful in a number of ways.

  • Identify the primary chords of a key.
  • Find chords that sound good together.
  • Work out the key of a song.
  • Transpose music from one key to another.
  • Find notes to build major chords.

What is a primary chord?

Firstly, you can use the Circle of Fifths to find the most important chords in a key. Usually, each key has three chords that are the most important chords because they are pleasing to the ear when played in progression. As a result they’re called primary chords.

It’s handy to know the primary chords of the key you are playing because they the chords you are most likely to need. In fact, many songs can be played on ukulele using only the three primary chords. Once you have learnt the primary chords of a key, move on to learn the other chords.

Finding the primary chords of a major key

Primary chords are also called the first (I), fourth (IV) and fifth (V) chords because they are based on the first, fourth and fifth notes of a major or minor scale.

We’ll start with a major key.

If you know the notes of the major scale, it’s easy to find the first, fourth and fifth notes. Each major scale has eight notes. The first and last notes have the same name as the key. Simply count along until you find the fourth and fifth notes.

The primary chords of C Major

The notes of the C Major scale are C, D, E, F, G, A, B and C.

The first note is C, the fourth note is F, and the fifth note is G.


Keryn Henderson 202008_CmajorPrimaryChords

So C Major, F Major and G Major are the primary chords of a song played in the key of C Major.

At the top of the Circle of Fifths, you can see the three primary chords of C Major. F and G are either side of C.

Keryn Henderson 2020


Keryn Henderson 2020

On the Circle of Fifths, the IV and V chords are located either side of the I chord.

Can you work out what the primary chords of A Minor will be? Remember Am is the I chord.

Now, use the Circle of Fifths to find the primary chords of A Major, D Major and G Major.

Which chords sound good together?

Secondly, you can use the Circle of Fifths to find a set of chords that sound good together in each major and minor key.

The Circle of Fifths organises keys into groups that relate to each other musically.

Looking at C Major

On the outer circle, find the C segment at the top of the circle. Any chord that shares a boundary line with the C segment will work well in a song in C major key (F, G and Am).


Keryn Henderson 2020

The next closest chords, only touching the C segment at the corners (Dm and Em), should work too.

The further you move from the C, the less likely the chords will sound good together in that key.

This general ‘rule of thumb’ underpins a lot of musical compositions.

In the set of diagrams below, you can see how the chords that sound good together for some of the other major keys are organised on the Circle of Fifths.



Keryn Henderson 2020

Finding a song’s key

Another use of the Circle of Fifths is to identify the key of a song. Look at the sheet music. If you don’t have the sheet music, a quick Google image search should give you the first page.

Count the number of sharps or flats in the key signature.

Then go to the Circle of Fifths.

Start at the C segment. Remember, C Major and A Minor have no sharps or flats. Move clockwise for sharps and anticlockwise for flats. Count around the segments of the circle the same number of segments as there are sharps or flats in the key signature.

Remember to count C as zero.11_Circleof5ths


For two sharps, move two segments clockwise from C to D. So the key is either D Major or B Minor.





With one flat, move anticlockwise one segment from C to F. The key is F Major or D minor.

Find some sheet music. Use the Circle of Fifths to determine the name of the key.




Transposing keys

Sometimes a song you like is in a key that’s difficult for you to sing. Transposing the song to other keys is easy with the Circle of Fifths.


Keryn Henderson 2020

If a song is in C, the chords you are most likely to find are those in the C pie slice of the circle.

First of all, look for the primary chords — C, F, G & Am.






From C Major to F Major19_FMajorPieSlice

Transposing from C to F, find the corresponding chords in the F pie slice. For the primary chords, C becomes F, F becomes Bb, and G becomes C. The other chords changes are Dm to Gm, Am to Dm, and Em to Am.




21_GMajorPieSliceFrom C Major to G Major

Going from C to G, look for the corresponding chords in the G pie slice. The primary chords of C, F and G become G, C, D and Em. And Em becomes Bm, Am becomes Em, and Dm becomes Am.








Transposition table

If you’re transposing a song to a range of keys, it might be useful to refer to the Circle of Fifths and create a transposition table like this.


How do I find the notes to build a chord?

Those who enjoy fingerpicking, can use the Circle of Fifths to find the notes in chord. Then all they need to do is locate the notes on the ukulele fretboard.

Look at this table that lists the notes of each primary chord in the major keys.


But if you didn’t have this table, all you need is the Circle of Fifths.

If you look again at the Circle of Fifths, you’ll discover that the first note in C Major chord is the segment with the name of the chord (C). The other two notes in this chord are the second (G) and fifth segments (E) from the name of the chord.


When you need to know the notes in other major chords, you can use the Circle of Fifths to find the first, second and fifth segments.

Let’s put this to the test by comparing the notes we find for chords on the Circle of Fifths with the finger positions shown on ukulele chord diagrams for C, F and G major.

Ukulele fretboard diagram

To compare the information from the Circle of Fifths with ukulele chord diagrams, it will be handy to know the note positions on the ukulele fretboard.

A 12-fret ukulele fretboard diagram can be used to locate notes on soprano, concert and tenor ukuleles.


Keryn Henderson 2020

Notes on the fretboard

The dots on the left-hand side of the diagram are for G, C, E and A . These are the names of the strings, and the ‘open’ notes of the fretboard.

The dots between the fret bars on each string represent where to put a finger for each note.

The colour coding of the fretboard shows that each note can be found in a number of different places on the fretboard.

Dots for sharps and flats are shaded grey.

Finding notes to build C Major, F Major and G Major

Initially, we’ll use the Circle of Fifths to work out the notes in the chords. Remember, it’s the first, fifth and second from the name of the chord, counting the name of the chord as the first.

Then we’ll look at the ukulele chord diagrams to find out where we have to put our fingers on the ukulele fretboard in order to play the chord.

Finally, we’ll look at the ukulele fretboard diagram to see what notes we’re playing when we place our fingers in those positions.