Finding Chords With the Circle of Fifths

So the Circle of fifths is the most common graphic organizer used in music. It is an orderly and functional way of sorting Major and minor key signatures. It gets it's name by the fact that moving clockwise around the circle by the interval of a fifth identifies key signatures incrementally.

Here is that famous graphic organizer...

In this case the circle shows the Major keys (outer ring letters) and the minor keys (inner ring letters) and the key signature for each (far outer layer).

For example, the key of G Major (and e minor) has one # in the key signature (F#) so the notes in G Major are: G, A, B, C, D, E, F#. Those are also the same notes you would find in e minor, just in a different order: E, F#, G, A, B, C, D.

This is helpful when trying to identify the chords in any key. The chords in a Major key have the same quality regardless of the key signature. Quality refers the whether the chord is Major or minor (or sometimes...diminished or augmented). Here is the list of chord qualities in a Major scale:

I- Major

ii- minor

iii- minor

IV- Major

V- Major

vi- minor

viio- diminished

If we apply this to G Major this is what we get:

I- Major = G
ii- minor = Am
iii- minor = Bm
IV- Major = C
V- Major = D
vi- minor = Em
viio- diminished = F#o

Musicians will use this knowledge to help when working out chords to songs. Since a great deal of music focuses around the primary chords (I, IV, V), knowing what keys these chords come from will help you find other chords in a song you want to play. Additionally, songwriters understand the relationship between these chords and will use this information when putting together chord progressions for songs.