The circle of fifths is a powerful tool in learning music theory with lots of information packed in a small space. If you haven’t really used the circle before, there’s no better time to start than now!

In this mini-lesson, I’ll cover some a couple of great uses for the circle / cycle including how to find relative major / minor keys, basic progressions, learning the sharps / flats per key, and how to spell some basic chords – and that’s just the beginning!

Below is a basic version of the circle we’ll use for this example. I would suggest printing a copy of the circle out and hanging it in your practice area as a quick reference.

Circle of 5ths / Cycle of 4ths – First let’s clear up the name! While generally the above is referred to as the Circle of 5ths, it’s also called the Cycle of 4ths. Don’t panic – they are the same thing. The only real difference is the direction you move.

• For the Circle of 5ths – starting at C, move right and you’ll get G which is the 5th of C. Each movement right is a 5th.
• For the Cycle of 4ths – starting at C, move left and you’ll get F which is the 4th of C. Each movement left is a 4th.

Below is a short list of the cool things you can learn from the circle.

Relative Major and Minor
Most circles will show the Major key on the outside with its relative Minor key on the inside. For example, as noted in the picture above, C’s relative minor is A minor. Remember:

• the 6th degree (or vi) of any Major key is its relative Minor.  Starting with C, move three spaces right in the circle and you’ll land on A, which is the relative Minor of C

• The 3rd degree (or iii) of any Minor key is its relative Major. Starting with A, move three spaces left in the cycle and you’ll land on C, which is the relative Major of A

Progressions

• 1 4 5 (I IV V) – The chord to the left and right of any particular key will make up a 1 4 5 (or I IV V) progression. For example, from C (the root) move left one away from C and you’ll get the F (the 4 or IV), then move right one away from C and you’ll get G (the 5 or V)

• 6 2 5 1  – This common jazz turnaround is just a progression of 4ths. For any key, start with the 6th of that key and move left on the circle. For example, a 6 2 5 1 (or vi ii V I) in C would be Am Dm G7 C. Starting on the A, just move back stepwise to C.
  • Something to note, often times a 6 2 5 1 is shifted to all major (or A D G C or VI II V I) or dominant chords (A7 D7 G7 C7 or VI7 II7 V7 I7).  This includes the smaller 2 – 5 – 1 (i.e. D G C or D7 G7 C7) change and 5 – 1 changes (G C or G7 C7).

Sharps / Flats
Knowing what notes are sharp and flat in a given key is really helpful – especially if you have to transpose a song to a new key. The circle of fifths makes learning this really easy.

• Moving right increases the number of sharps by one and the new sharp will be the 7th note of that key. For example, C has no sharps, move right one space to G and you’ll add 1 sharp (F# the 7th of G), move right again to D and you’ll add another sharp to the F# (C# the 7th of D) for a total of 2 sharps (F# and C#), move right again to A you’ll add another sharp (G# the 7th of A) for a total of 3 sharps (F#, C#, and G#) etc
• Moving left increases the number of flats by one and the new flat will be the 4th note of that key. For example, C has no flats, move left one space to F you’ll add one flat (Bb the 4th of F), move left again to Bb and you’ll add another flat (Eb the 4th of Bb) for a total of 2 flats (Eb and Bb), move left again to Eb and you’ll add another flat (Ab the 4th of Eb) for a total of 3 flats (Bb, Eb, and Ab) etc

Spelling Chords
Using the circle as a visual reference can be helpful when trying to remember how to spell chords.

• Major – Starting with any Major key (on the outside of the circle), the relative minor of the 5th above will be the 3rd of the root. That may sound complex, but looking at the picture below starting at C – the 5th of C is G and the relative minor of G is Em. So, that’s C E G to spell C major.
• Major 7th – to the above, just add the relative minor of the 2nd chord. In this example, the 2nd of C is D and the relative minor of D is Bm – so the relative major would be C E G B which is how to spell Cmaj7.

• Minor – Starting with any Minor key (on the inside of the circle), that notes relative Major will be the 3rd and the minor a 5th above is the 5th. So looking at A Minor, the relative major is C so that’s the 3rd. The 5th above is E Minor, so E is the 5th. So A Minor is A C E.
• Minor 7th – to the above, add the relative major of the 5th. So in A Minor, that would be adding the G. So A Minor 7th would be A C E G.

Just the beginning

While the above is a good start, there’s SO much more to the circle than this. I would suggest you spend some time reviewing the circle / cycle and seeing what other patterns you can find. If you’re interested in a more deep dive on the circle, check out my personal coaching page.

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