The circle of fifths is an incredibly useful tool that all musicians should be familiar with, regardless of the instrument and musical genres they play, as the information it conveys is useful in any musical scenario.
Before we get into very specific details, just be aware that the circle of fifths can also be called circle (or cycle) of fourths, depending on whether you’re going through it clockwise or anti-clockwise.
In a very summarized way, this circle is a visual representation of the relationship and connections that exist between all 12 keys – major, minor, sharps and flats, and it provides you with all of the important information you should be aware of, such as the accidentals (sharps/flats) in each key, the relative minor scales of each major key, and more.
While it looks a little intimidating at first, mastering the circle of fifths is not hard as it seems, and by doing so, you’ll gain a much deeper understanding of music in general.
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The Circle of Fifths at a Glance
The most important details to be aware of when interpreting the circle of fifths are the following:
- If you follow the circle clockwise, you’ll cover all of the major keys, separated by a perfect fifth interval (A fifth up from C is G, then D, A, and so on);
- If you follow it in an anti-clockwise direction instead, you can call it the circle of fourths, as every key is separated by a perfect fourth interval (A fourth up from C is F, then Bb, Eb, and so on);
- The keys you see on the outer side of the circle are the major keys, and the ones on the inner side are the minor keys;
- Each pair of two keys you see have a relation between them. For example, C Major is the relative major scale of A minor, meaning they share the same notes (same sharps/flats). You’ll find the relative minor scale a major sixth above its major counterpart, or one minor third below it;
- Next to each key, you’ll see the key signature as you would have to write it in sheet music. This is useful because besides being able to see what notes are sharp or flat in each key, you also get a very clear vision of which keys are most similar to one another;
For instance, you can see that G Major is very similar to C Major, the only difference is that you have F# in G Major, whereas in C Major you have F natural.
Another important fact about the circle of fifths (and the way that key signatures are used in general) is that some keys are written in a certain way because it simplifies them.
For example, there is no E# Major or B# Major. These would be F and C Major, respectively. Writing them this way means there will be less sharps/flats on the sheet music, making it much easier to read.
The same happens with keys such as B♭ Major – it is much easier to write and read than A#, despite having the exact same sound.
Take a little time to look at each key one at a time, and you’ll see that it encompasses every possible one, just not in the order you are used to.
Figuring Out the Sharps and Flats of Each Key
While this circle might appear to be complex and difficult to interpret, it follows simple and straightforward rules. Let’s start with how you should add sharps or flats to the key signature according to the direction you’re moving in.
As you keep moving in perfect fifths in a clockwise direction, you add a sharp to the key signature with each step you take. The order in which you must add sharps is always the same:
- # F C G D A E B
You must do this from C until you reach F#, which covers 7 of the 12 existing keys.
If you move anti-clockwise instead, you must add flats. Remember, there aren’t any keys that have BOTH sharps and flats at the same time.
The order in which you add flats is also the same every time:
- ♭ B E A D G C F
Doing this will cover the remaining 5 keys. Keep in mind that F# and G♭ have the same meaning, and frequently appear in the circle of fifths written both ways.
If you look closely, you’ll see that the rule for adding flats is the same as for the sharps, but inverted. There are a few tricks you can use to memorize these two sequences, such as sentences in which each letter corresponds to a word. For instance, these are two common examples:
- # Father Charlie Goes Down And Ends Battle
- ♭ Battle Ends And Down Goes Charles Father
In any case, knowing these intervals by heart is much more useful in the long run, so be sure to give it a try.
What Else is the Circle of Fifths Useful For?
Songwriting – Aside from being such a great visual representation of how keys are connected to each other, the circle of fifths can be one of your best friends when you’re composing.
Generally, if you want to change to a different key in a song, it is always easier to “modulate” into a key that is one or at most, two positions in the circle.
For instance, if you’re in C Major, G Major or F Major are great keys to consider as they only have one different note from the first key center. (F# instead of F natural in G Major, and B♭ instead of B in F Major).
Modulating into a key that is inherently more distinct than the one you’re coming from will require a lot more effort to avoid sounding too “abrupt” when the key change occurs.
Also, being able to keep track of what is the relative major/minor scale of the key you’re in will allow you to move between major and minor more seamlessly.
Practicing – Studying your instrument while following the circle of fifths is a bulletproof method if you want to cover that exercise in all 12 keys.
By repeating whatever it is you’re playing (it could be a scale, arpeggios, a musical phrase, a chord progression, etc.) and cycling through the keys according to the circle of fifths, you’re making yourself comfortable with that vocabulary in every key, which in the long term should make you a much more complete musician in general.
You can also use the circle of fifths to find the key of a song – more on that here.
Final Thoughts on the Circle of Fifths
To summarize, investing some time into mastering the circle of fifths not only makes you understand how music and harmony work a lot better, but it will also allow you to use it to compose better songs, practice anything you want with a foolproof method, and much more.
Like any other new music theory concept, it can seem a little overwhelming when you start studying it, but after getting comfortable with moving in fifths and in fourths, it all becomes very intuitive.