Pitch & Intervals

Minor Seventh

Written as m7

Definition

A minor seventh (m7) is an interval of ten half steps spanning seven letter names, such as G–F, D–C or C–B♭. It is the seventh of a dominant seventh chord and sounds tense but mellow.

A minor seventh spans seven letter names and ten half steps: G up to F, D up to C, E up to D, C up to B♭. Abbreviated m7, it measures 1000 cents in equal temperament.

Three one-bar examples of three half notes each: the lower note, the upper note, then both together. G4 and F5, D4 and C5 in treble clef; C3 and B flat 3 in bass clef. — Three minor sevenths, each shown in one bar: the lower note, the upper note, then both together. G–F and D–C in the treble clef, C–B♭ in the bass clef.

Counting it

G–A–B–C–D–E–F is seven letters, so G–F is a 7th. The quick way to size a 7th is "an octave minus a 2nd": G up to the next G is 12 half steps, and F lies a whole step (2 half steps) below that upper G. So G–F is 12 − 2 = 10 half steps, a minor seventh. If the top note is only a half step below the octave, the interval is a major seventh.

From C, count every key up to B♭: ten half steps make a minor seventh, two short of the octave.

Five of the seven white-key 7ths are minor: D–C, E–D, G–F, A–G and B–A. Only C–B and F–E are major.

The sound of the dominant seventh

The minor seventh is the defining interval of the dominant seventh chord: in G7 (G–B–D–F), the root G and the seventh F are a minor seventh apart. It is also the outer interval of the minor seventh chord (Dm7: D–F–A–C) and the half-diminished seventh chord. In blues, rock and funk the minor seventh above the root is so common that a plain "7" chord can sound settled rather than tense.

In classical harmony the minor seventh is a dissonance, milder than a major seventh or a minor second. In a dominant seventh chord the seventh usually resolves down by step: when G7 moves to C, the F falls to E.

Hearing it

A rising minor seventh opens the song "Somewhere" from West Side Story (on "There's a"). Another route is to imagine the octave, then step down a whole step. In the harmonic series, the 7th harmonic sounds a minor seventh (plus two octaves) above the fundamental, but about 31 cents lower than the piano's version.

Inversion and look-alikes

Inverted, a minor seventh becomes a major second: G–F becomes F–G, and 10 + 2 = 12. The same keys spelled with six letter names, such as C–A♯, form an augmented sixth, the interval that gives the augmented sixth chord its name.

Practice with The 6th, the 7th & the Octave and Invert the intervals.

Common questions

How many half steps are in a minor seventh?

Ten. It is an octave (12) minus a whole step (2).

What is the difference between a minor seventh and a minor seventh chord?

The minor seventh is an interval between two notes, such as C–B♭. A minor seventh chord is a four-note chord, such as Cm7 (C–E♭–G–B♭), whose outer notes form that interval. A dominant seventh chord (C7: C–E–G–B♭) contains the same interval.