A Majeur Accord

A bright, happy triad built from a root, major third, and perfect fifth.

A Accord — Quick Answer & Harmonic Definition

The A (Major) chord consists of the notes A, C#, E. It is constructed from the root note A using the major interval formula (0–4–7 semitones).

Formula: 0 – 4 – 7

Notes

A – C# – E

Intervals (semitones)

0 – 4 – 7

Type

Triad

A on Piano

Press highlighted keys simultaneously to play the A chord.

A (Root (R))

C# (Major 3rd)

E (Perfect 5th)

A on Guitar

Fret numbers (low E → high e string): x02220 (x=mute, 0=open)

Interval Analysis

Degree	Interval Name	Semitones	Note in A
Root	Root (R)	0	A
3rd	Major 3rd	4	C#
5th	Perfect 5th	7	E

About the A Majeur Chord

The A chord (A Majeur) consists of 3 notes: A, C#, E. A bright, happy triad built from a root, major third, and perfect fifth.

To build any major chord, apply intervals of 0, 4, 7 semitones above the root. Starting from A: the notes land on A, C#, E.

Playing A on Piano

Press A, C#, E simultaneously. In root position, A is lowest. First inversion places C# in the bass for a lighter sound; second inversion uses E as the bass note.

Common Chord Progressions Using A

I–IV–V: A – D – E (blues and rock)
I–V–vi–IV: A – E – F#m – D (pop staple)
I–vi–IV–V: A – F#m – D – E (50s progression)

The A Chord in Context

As a major chord, A serves as the tonic (I) in the key of A major. It also appears as the IV chord in E major, and as the V chord in D major — making it one of the foundational primary triads in Western harmony.

Other A Chords

Majeur Chord in All 12 Keys

C C# D D# E F F# G G# A A# B

Knowledge Base & FAQs

A Chord — Frequently Asked Questions

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What notes are in the A chord?

The A Majeur chord contains: A, C#, E.

These notes are derived by applying the major interval formula (0–4–7 semitones) to the root note A.

What is the A chord used for?

A bright, happy triad built from a root, major third, and perfect fifth.

The A chord is used across pop, rock, jazz, and classical music. As the I chord in the key of A major, it functions as the most stable resting point in progressions.

How do you play A on piano?

On piano, play A, C#, E simultaneously.

In root position, A is the lowest note. Inversions move the bass note up — first inversion has C# lowest, second inversion has E lowest.

How many notes are in a major chord?

A major chord has 3 notes: A, C#, E (in A).

It is a triad — the most fundamental chord type.

What is the difference between A major and A minor?

The A major chord (A–C#–E) uses a major third (4 semitones), giving it a bright, happy sound.

The A minor chord (A–C–E) uses a minor third (3 semitones), giving it a darker, emotional sound.

What key does A belong to?

A naturally serves as the I chord in the key of A major.

It also appears as IV in the key of E major, and as V in the key of D major.

Can I play A on ukulele?

Yes.

The ukulele uses GCEA tuning with 4 strings. The A chord notes (A, C#, E) can be fretted on a ukulele, though the shapes differ from guitar due to the 4-string layout and shorter scale.

What chords go well with A?

In the key of A major, A pairs naturally with D major (IV), E major (V), and F#m (vi).

The classic I–IV–V (A–D–E) is the foundation of blues, country, and rock.

What is a chord inversion of A?

An inversion places a non-root note in the bass.

A root position: A in bass. First inversion: C# in bass. Second inversion: E in bass. Inversions create smoother bass line movement without changing the harmony.

How do I memorize the notes in a major chord?

Remember the formula: 0–4–7 semitones from root.

For A: start on A, add 4 semitones, then 7 semitones. Practicing this across all 12 roots builds instant recognition of any major chord.