Circle of Fifths

In music theory, the circle of fifths (sometimes also cycle of fifths) is a way of organizing pitches as a sequence of perfect fifths.

Starting on C, and using the standard system of tuning for Western music (12-tone equal temperament), the sequence is:

C, G, D, A, E, B, F♯/G♭, C♯/D♭, G♯/A♭, D♯/E♭, A♯/B♭, F, C

This order places the most closely related key signatures adjacent to one another.

Twelve-Tone Equal Temperament

Twelve-tone equal temperament tuning divides each octave into twelve equivalent semitones.
The circle of fifths leads to a C seven octaves above the starting point.

Definition

The circle of fifths organizes pitches in a sequence of perfect fifths, generally shown as a circle with the pitches (and their...