D Major 7th
maj7
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About D Major 7th
D major seventh is one of the guitar’s easiest four-note chords: the standard D triangle with the C♯ added at the second fret of the high E string. Two of the four notes come from open strings, and the result is bright, still and slightly wistful.
The notes
D, F♯, A, C♯. The C♯ is a semitone below the octave D, and that half step is the entire character of a major seventh — present but unhurried.
Lower it to C and the chord becomes D7, which pulls hard toward G. The pair sits at the second fret of the same string, one fret apart, doing opposite jobs.
On the fretboard
The open shape is a D with the high E fretted at the second rather than the third fret. It is easier than plain D, which is unusual for a seventh chord and explains its popularity in acoustic writing.
A fuller version adds the low D at the fifth fret of the A string, giving the chord a bass note the open shape lacks.
Where it shows up
As the I of D major and the IV of A. Both keys are guitar keys, so the chord appears constantly in folk and singer-songwriter material where a plain D would sound too settled.
In jazz it closes the ii–V–I in D: Em7, A7, Dmaj7 — and the open voicing is one of the few places where a jazz cadence can be played with ringing strings.
It is also the chord that teaches the difference between colour and function. Swap Dmaj7 for D in a folk progression and nothing breaks; swap it for D7 and the song changes direction. One note distinguishes all three.