Guitar chords in the key of D major:
D Em F#m G A Bm C#dim

Chord Ddim7 (10th fret) notes: Ab, D, F, B and D. You should not play the 6th string.

This chord is played by placing a barre on fret ten with your index finger.

Ddim7 - D diminished seventh guitar chord's alternative names: D°, D°7, Do7, D7dim. See also: Ddim and Dm7b5.

Steps: 1-b3-b5-6(or bb7).
1(D), b3(F), b5(G#/Ab), 6(B).