What is a Half-diminished Chord?

Minor 7 flat 5 chord is close to a diminished 7th chord, the first 3 notes are identical, but the 4th is different. This chord can be written in two ways: m7b5 or Ø. If you do not know how to play and what is a diminished 7th chord, you can read this page about diminished chord voicings.

As is it shown in the chart below, the half-diminished chord is built with a root (1), a minor third (b3), a flat fifth (b5) and a minor 7th (b7). The diminished 7th chord has a diminished 7th instead of the minor seventh. This is the only difference between these two chords.

Half-diminished 7th chord 1 b3 b5 b7 Diminished 7th chord 1 b3 b5 bb7

You can find the half-diminished chord in a number of harmonized scales. For example the 7th degree of the major scale, the 2nd degree of the harmonic minor scale and the 6th and 7th degree of the melodic minor scale.

The major harmonized scale

When you harmonize in thirds the degree VII of the major scale you obtain a m7b5 chord.

Degrees I II III IV V VI VII C major scale C D E F G A B Quadrad chords CMaj7 D-7 E-7 FMaj7 G7 A-7 B-7b5

The harmonic minor harmonized scale

When you harmonize in thirds the degree II of the harmonic minor scale you get a m7b5 chord.

Degrees I II III IV V VI VII C Harmonic minor scale C D Eb F G Ab B Quadrad chords C-maj7 D-7b5 EbMaj7#5 Fm7 G7 AbMaj7 Bdim7

The melodic minor harmonized scale

When you harmonize in thirds the degrees VI and VII of the major scale you obtain two m7b5 chords.