The A 7♯5 chord is a four-note chord made up of A, C♯, E♯, and G. It is built from a root, major third, augmented fifth, and minor seventh.
Construction
| Note | Interval | Degree |
|---|---|---|
| A | Root | 1 |
| C♯ | Major 3rd | 3 |
| E♯ | Minor 6th | ♯5 |
| G | Minor 7th | ♭7 |
A 7♯5 Inversions



| Position | Notes |
|---|---|
| Root Position | A – C♯ – E♯ – G |
| 1st Inversion | C♯ – E♯ – G – A |
| 2nd Inversion | E♯ – G – A – C♯ |
| 3rd Inversion | G – A – C♯ – E♯ |
Key Signature
A chord has no key signature of its own, but the A 7♯5 is the tonic (I) chord of A Major, whose key signature has 3 sharps (F♯, C♯, G♯).
Order of sharps
Sharps are added to a key signature in a fixed order. Each new sharp key adds the next sharp on the list.
Mnemonic: Father Charles Goes Down And Ends Battle
Chords in the Key of A Major
These are the triads built on each degree of the A major scale:
Same Notes, Other Names
The notes A – C♯ – E♯ – G aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell: