Pitch & Intervals

Major Seventh

Written as M7

Definition

A major seventh (M7) is an interval of eleven half steps spanning seven letter names, such as C–B, F–E or B♭–A. Just a half step short of an octave, it is sharply dissonant, yet it gives maj7 chords their glow.

A major seventh spans seven letter names and eleven half steps: C up to B, F up to E, G up to F♯, B♭ up to A. Abbreviated M7, it measures 1100 cents in equal temperament, one half step short of an octave.

Three one-bar examples of three half notes each: the lower note, the upper note, then both together. C4 and B4, F4 and E5 in treble clef; B flat 2 and A3 in bass clef. — Three major sevenths, each shown in one bar: the lower note, the upper note, then both together. C–B and F–E in the treble clef, B♭–A in the bass clef.

Counting it

C–D–E–F–G–A–B is seven letters, so C–B is a 7th. Instead of counting eleven keys, think "an octave minus a half step": C up to the next C is 12, and B is a half step below that upper C, so C–B is 11 half steps. A minor seventh is a whole step short of the octave.

From C, count every key up to B: eleven half steps make a major seventh, one short of the octave.

Only two white-key 7ths are major: C–B and F–E. The others need a sharp on top or a flat at the bottom: G–F♯, D–C♯, B♭–A.

How it sounds

Played together, a major seventh is one of the sharpest dissonances: the top note sits a minor second below the octave of the bottom note, and the two grind. Yet in a full chord it can sound lush. The major seventh chord (Cmaj7: C–E–G–B) adds a major seventh to a major triad, and its soft, dreamy sound is a staple of jazz, bossa nova and ballads. How harsh it sounds depends on context and voicing: with the C low and the B high, the clash turns into color.

In a major key, the leading tone lies a major seventh above the tonic (B above C) and a half step below the next tonic, which is why it pulls upward so strongly.

Hearing it

As a melodic leap, a rising major seventh is wide and dramatic, and few well-known tunes start with one. A reliable trick is to imagine the octave above the first note, then come down one half step.

Inversion and look-alikes

Inverted, a major seventh becomes a minor second: C–B becomes B–C, and 11 + 1 = 12. The same keys spelled with eight letter names, such as C–C♭, form a diminished octave, which is rare.

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

Common questions

How many half steps are in a major seventh?

Eleven: one half step less than an octave.

Why does a major seventh chord sound pleasant if the interval is dissonant?

In a Cmaj7 chord the dissonant B is surrounded by consonant notes (C–E–G), and players often spread the chord so that C and B are far apart. The clash becomes a soft shimmer rather than a grind, which is why jazz and pop musicians use maj7 chords as restful, even final, sounds.