F♯ Augmented Chord (F#aug, Gbaug) on Piano
The F#aug chord (F# augmented) is built from 3 notes: F# – A# – C##. It is also written as Gbaug.
Play these notes on a MIDI keyboard, your computer keyboard, or the on-screen keys and ChordKeys will name the chord back to you.
Notes and intervals
| Note | Degree | Interval from F# | Semitones |
|---|---|---|---|
| F# | 1 | root | 0 |
| A# | 3 | major 3rd | 4 |
| C## | #5 | augmented 5th | 8 |
Inversions
Rearranging which note sits at the bottom gives you 3 playable voicings of the same chord. Inversions let you move between chords with less hand movement.
| Voicing | Notes | Bass note |
|---|---|---|
| Root position | F# – A# – C## | F# in the bass |
| 1st inversion | A# – C## – F# | A# in the bass |
| 2nd inversion | C## – F# – A# | C## in the bass |
How the augmented chord is built
Every augmented chord uses the same interval formula: 1 (0 semitones), 3 (4 semitones), #5 (8 semitones). Starting on F# and applying that formula produces F#, A#, C##. Learn the formula once and you can build a augmented chord on any of the twelve roots.
Other chords on F#
Augmented chords on other roots
Frequently asked questions
What notes are in a F#aug chord?
A F#aug chord contains the notes F#, A#, C##. Those are the 1, 3, #5 degrees measured from the root note F#.
How do you play F#aug on piano?
Place your thumb on F#, then add A# and C## above it. With a right hand in root position the common fingering is 1–3–5.
Is F#aug the same as Gbaug?
Yes. F#aug and Gbaug are enharmonic equivalents — they sound identical and use the same piano keys. Which spelling you use depends on the key you are playing in.