What is a Diminished Scale?

A diminished scale is a type of symmetrical musical scale built from alternating whole steps and half steps. Because of this repeating pattern, the scale contains eight notes within an octave and is sometimes called an octatonic scale. The unique interval pattern gives the scale a tense and dramatic sound that is often used in advanced harmony and improvisation.

There are two common forms of the diminished scale. One begins with a whole step followed by a half step (whole–half pattern), and the other begins with a half step followed by a whole step (half–whole pattern). For example, a C diminished scale using the whole–half pattern would include the notes C, D, E♭, F, F♯, G♯, A, and B before returning to C.

Diminished scales are widely used in jazz, classical music, and modern film scoring. They are especially useful when playing over diminished chords or dominant chords with altered tones. Because the scale repeats its pattern symmetrically, it allows musicians to create complex melodic lines and dramatic harmonic effects in music.