A7 7ª Dominante Acorde

A major triad with a minor seventh. Creates harmonic tension that resolves to the tonic.

A7 Acorde — Quick Answer & Harmonic Definition

The A7 (Dominant 7th) chord consists of the notes A, C#, E, G. It is constructed from the root note A using the dominant 7th interval formula (0–4–7–10 semitones).

Formula: 0 – 4 – 7 – 10
Notes
A – C# – E – G
Intervals (semitones)
0 – 4 – 7 – 10
Type
7th Chord

A7 on Piano

Press highlighted keys simultaneously to play the A7 chord.

R
A (Root (R))
2
C# (Major 3rd)
3
E (Perfect 5th)
4
G (Minor 7th (♭7))

A7 on Guitar

Fret numbers (low E → high e string): x02020 (x=mute, 0=open)

x
E
0
A
2
D
0
G
2
B
0
e

Interval Analysis

Degree Interval Name Semitones Note in A
Root Root (R) 0 A
3rd Major 3rd 4 C#
5th Perfect 5th 7 E
7th Minor 7th (♭7) 10 G

About the A 7ª Dominante Chord

The A7 chord (A 7ª Dominante) consists of 4 notes: A, C#, E, G. A major triad with a minor seventh. Creates harmonic tension that resolves to the tonic.

To build any dominant 7th chord, apply intervals of 0, 4, 7, 10 semitones above the root. Starting from A: the notes land on A, C#, E, G.

Playing A7 on Piano

Press A, C#, E, G 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 A7

  • I–IV–V: A7 – D7 – E7 (blues and rock)
  • I–V–vi–IV: A7 – E – F#m – D (pop staple)
  • I–vi–IV–V: A7 – F#m – D – E (50s progression)

The A7 Chord in Context

The A7 (7ª Dominante) chord features a distinctive a major triad with a minor seventh. creates harmonic tension that resolves to the tonic. built from the intervals 0–4–7–10. It provides rich harmonic color and tension across pop, jazz, classical, and contemporary compositions.

Knowledge Base & FAQs

A7 Chord — Frequently Asked Questions

Everything you need to know about our browser-based Web Audio engine, instruments, and music theory workspace.

What notes are in the A7 chord?

The A 7ª Dominante chord contains: A, C#, E, G.

These notes are derived by applying the dominant 7th interval formula (0–4–7–10 semitones) to the root note A.

What is the A7 chord used for?

A major triad with a minor seventh.

Creates harmonic tension that resolves to the tonic. The A7 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 A7 on piano?

On piano, play A, C#, E, G 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 dominant 7th chord?

A dominant 7th chord has 4 notes: A, C#, E, G (in A).

It is a 7th chord, extending beyond the basic triad.

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 A7 belong to?

A7 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 A7 on ukulele?

Yes.

The ukulele uses GCEA tuning with 4 strings. The A7 chord notes (A, C#, E, G) 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 A7?

In the key of A major, A7 pairs naturally with D major (IV), E major (V), and F#m (vi).

The classic I–IV–V (A7–D–E) is the foundation of blues, country, and rock.

What is a chord inversion of A7?

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

A7 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 dominant 7th chord?

Remember the formula: 0–4–7–10 semitones from root.

For A7: start on A, add 4 semitones, then 7 semitones, then 10 semitones. Practicing this across all 12 roots builds instant recognition of any dominant 7th chord.