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Key cheat sheet

A Major

A major has 3 sharps. Its relative minor is F#m and its parallel key is Am. This page lists the signature, scale notes, diatonic chords, and go-to progressions, with tools that play the sound.

Key signature

Sharps: 3 (Notes: F#, C#, G#)

C G D A E B F# Db Ab Eb Bb F Am Em Bm F#m C#m G#m D#m Bbm Fm Cm Gm Dm
A — Key signature

Scale notes

The notes that make up this scale, shown with their degrees.

DEABC#F#G#
A メジャー(長音階)
Degree 1234567
Note ABC#DEF#G#

Diatonic chords

The chords that belong to this key, color-coded by role: T (tonic), SD (subdominant), D (dominant).

Triads

Degree Chord Notes Function
A A C# E T
Ⅱm Bm B D F# SD
Ⅲm C#m C# E G# T
D D F# A SD
E E G# B D
Ⅵm F#m F# A C# T
Ⅶdim G#dim G# B D D

Seventh chords

Degree Chord Notes Function
Ⅰmaj7 Amaj7 A C# E G# T
Ⅱm7 Bm7 B D F# A SD
Ⅲm7 C#m7 C# E G# B T
Ⅳmaj7 Dmaj7 D F# A C# SD
Ⅴ7 E7 E G# B D D
Ⅵm7 F#m7 F# A C# E T
Ⅶm7b5 G#m7b5 G# B D Gb D

Related keys

Go-to progressions in this key

Common progressions written out with the real chord names for this key. Play them in the progression player to hear them.

Progression Chords
Royal Road Progression D - E - C#m - F#m ▶ Play in player
Canon Progression A - E - F#m - C#m - D - A - D - E ▶ Play in player
Komuro Progression F#m - D - E - A ▶ Play in player

Hear it with the tools

Links that open each tool preset to this key.

Related articles

Articles for anyone who wants to understand keys and signatures more deeply.