F b5
The F b5 chord consists of the F (Perfect unison), A (Major third) and B (Diminished fifth) notes.

How to play the F b5 chord
- Find F (Root) on the piano keyboard
- Add A (Major third) — 4 semitones above F
- Add B (Diminished fifth) — 6 semitones above F
- Press all 3 notes simultaneously to sound the F b5 chord