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New Released in April 2026

A Augmented Chord on Piano (Aaug)

The A augmented chord (Aaug) on the piano has three notes: A, C#, E#. It is a major triad with a raised fifth, formula 1 3 #5, built from two major thirds. Here is where Aaug comes from, where it resolves and how to play it with both hands.

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Aaug A C# E#

Aaug compared with A, Am and the other triads

Same root, same third or fifth moved by a semitone.

Chord	Notes	Third	Fifth
A	A C# E	major 3rd	perfect 5th
Am	A C E	minor 3rd	perfect 5th
Adim	A C Eb	minor 3rd	diminished 5th
Aaug	A C# E#	major 3rd	augmented 5th

Aaug in keys and progressions

Aaug is the III+ chord in the harmonic minor scale of F# minor.
Its thirds are equal, so Aaug, C#aug and Faug use the same three keys: the root is whichever note you treat as home.
A common move is A → Aaug → D: the raised fifth E# pushes up to F#.

D · A

Aaug on the keyboard: three positions

Move the lowest note up an octave to reach the next position.

Aaug A C# E#

Root position: A C# E#

Aaug C# E# A

1st inversion: C# E# A

Aaug E# A C#

2nd inversion: E# A C#

Root position: starts on A, a white key; black keys: C#
1st inversion: starts on C#, a black key; black keys: C#
2nd inversion: starts on E#, a white key; black keys: C#

ChordRunner showing a chord block while hands play the piano

Train Aaug in a game

ChordRunner mixes Aaug with the chords around it and checks every note you play. MIDI keyboard or microphone, both work.

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All piano chords · Augmented chords explained

Common questions

How do you play Aaug on the piano?

Press A, C#, E# together: right hand 1-3-5 with the thumb on A, left hand 5-3-1 with the little finger on A.

What is the difference between Aaug and A?

One note. A has E on top; Aaug moves it to E#. The new fifth is what gives Aaug its floating, unresolved sound.

Where does Aaug go?

Aaug is the III+ chord in the harmonic minor scale of F# minor. Its thirds are equal, so Aaug, C#aug and Faug use the same three keys: the root is whichever note you treat as home.

Can I practise Aaug with a MIDI keyboard or microphone?

Yes. ChordRunner detects a USB MIDI keyboard automatically and also hears an acoustic piano through the microphone. Aaug counts in any position, as long as A, C#, E# sound together.

Your instrument is the controller.

ChordRunner is a browser game that teaches piano and guitar chords: a chord appears on screen, you play it on a real instrument, and your runner jumps. MIDI keyboard or microphone, both work.

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A Augmented Chord on Piano (Aaug)

Aaug compared with A, Am and the other triads

Aaug in keys and progressions

Aaug on the keyboard: three positions

Train Aaug in a game

Common questions

How do you play Aaug on the piano?

What is the difference between Aaug and A?

Where does Aaug go?

Can I practise Aaug with a MIDI keyboard or microphone?

Your instrument is the controller.

Keep learning

A Major Chord on Piano (A)

A Minor Chord on Piano (Am)

A Diminished Chord on Piano (Adim)

Augmented Chords Explained

Piano Chord Chart: Every Chord in All 12 Keys

Chord Training That Feels Like a Game