F augmented chord (Faug)

The F augmented chord (Faug) is an augmented triad: F, A and C♯, two major thirds stacked on top of each other (root, major third and augmented fifth).

Because it splits the octave into three equal major thirds, F augmented has the same notes as A augmented and D♭ augmented; only the bass note changes.

With F, A and C♯, F augmented does not fit any major or natural minor scale: it is the chord on the third degree (III+) of the harmonic minor scale and is mostly used as a passing chord, as in I–I+–IV.

Below: voicings, notes on the fretboard, ukulele, piano and inversions.

How to play F augmented on guitar

There are 2 guitar voicings.

Frets from the 6th string to the 1st: x = not played, 0 = open string.

  • Voicing 1: 1-4-3-2-2-1, barre at fret 1, with F in the bass (fingers 1-4-3-2-2-1).
  • Voicing 2: x-8-7-6-6-x, with F in the bass (fingers x-4-3-1-2-x).

Notes of the F augmented chord on the fretboard

F augmented has 3 notes: F, A and C♯. This is where they fall on each string, from the nut to the 12th fret (fret number in parentheses):

  • String 6 (E): F (1) · A (5) · C♯ (9)
  • String 5 (A): A (0) · C♯ (4) · F (8) · A (12)
  • String 4 (D): F (3) · A (7) · C♯ (11)
  • String 3 (G): A (2) · C♯ (6) · F (10)
  • String 2 (B): C♯ (2) · F (6) · A (10)
  • String 1 (E): F (1) · A (5) · C♯ (9)

Formula and intervals of F augmented

Its formula is 1-3-♯5; in semitones from the root, 0-4-8.

  • F: Root, the note that gives the chord its name
  • A: Major third (M3), 4 semitones above F
  • C♯: Augmented fifth (A5), 8 semitones above F

F augmented on ukulele

  • Ukulele (G C E A): 2-1-1-0, barre at fret 1; it sounds A, C♯, F and A.

F augmented on piano

  • Keys: F4, A4 and C♯5.

Inversions of F augmented

Each inversion puts a different note in the bass.

  • Root position: F, A and C♯, with F in the bass.
  • First inversion (Faug/A): A, C♯ and F, with A in the bass.
  • Second inversion (Faug/C♯): C♯, F and A, with C♯ in the bass.

Keys that use F augmented

F augmented (F, A and C♯) is not a diatonic chord of any major or natural minor key. The augmented fifth does appear in the harmonic and melodic minor scales, where F augmented is the chord on the third degree.

Progressions with F augmented

  • Augmented passing chord in F major (I–I+–IV): F – Faug – B♭

Frequently asked questions

What notes are in the F augmented chord?

F, A and C♯: root, major third and augmented fifth. Its formula is 1-3-♯5.

Why does F augmented sound the same as A augmented and D♭ augmented?

Because the augmented chord divides the octave into three major thirds: F, A and C♯. When you invert it, the bass note changes but the notes stay the same distance apart, so F augmented uses the same keys and frets as A augmented and D♭ augmented.

What is the F augmented chord used for?

Mostly as a passing chord, as in I–I+–IV: on the same root, the fifth of the major triad rises a half step, giving F, A and C♯, which pushes toward IV. It is also the III+ of the harmonic minor scale.