What is the Circle of Fifths in Music Theory?
The Circle of Fifths also known as the Cycle of Fifths or Circle/Cycle of 4ths, is a visual representation of the relation and order of musical keys. It helps you understand music theory relationships of scales and keys and how many sharps and flats occur in each key.
Circle of 5ths mechanics
- In each direction around the circle either a sharp or flat is added to create the new key.
- The new key created takes the name of the 5th of the previous key in the sharp direction or the 4th of the previous key in the flat direction.
- Going in the sharp direction the 7th degree gets the sharp. Example: G Major gets an F#.
- Going in the flat direction the 4th degree gets the flat. Example: F Major gets a Bb.
- Enharmonic keys have two names for a key that has the same notes. There is really only 12 keys. Three of the keys can go by a different name.
The Number of Sharps in sharp keys
C Major / A minor - no sharps or flats
G Major / E minor - 1 sharp
D Major / B minor - 2 sharps
A Major / F# minor - 3 sharps
E Major / C# minor - 4 sharps
B Major / G# minor - 5 sharps
F# Major / D# minor - 6 sharps
C# Major / A# minor - 7 sharps
The Number of Flats in flat keys
F Major / D minor - 1 flat
Bb Major / G minor - 2 flats
Eb Major / C minor - 3 flats
Ab Major / F minor - 4 flats
Db Major / Bb minor - 5 flats
Gb Major / Eb minor - 6 flats
Cb Major / Ab minor - 7 flats
See Also: An in depth Circle of Fifths article on Wikipedia