D 11/F#
The D 11 chord consists of the D (Perfect unison), F# (Major third), A (Perfect fifth), C (Minor seventh), E (Major ninth) and G (Perfect eleventh) notes, with F# as the bass note.

How to play the D 11/F# chord
- Play F# as the lowest bass note in the left hand
- Find D (Root) on the piano keyboard
- Add F# (Major third) — 4 semitones above D
- Add A (Perfect fifth) — 7 semitones above D
- Add C (Minor seventh) — 10 semitones above D
- Add E (Major ninth) — 14 semitones above D
- Add G (Perfect eleventh) — 17 semitones above D
- Press all 7 notes simultaneously to sound the D 11/F# chord