A Chromatic Scale

Notes in the A Chromatic Scale

Interval Pattern

Harmony

The chromatic scale contains all 12 pitch classes and has no diatonic harmony — all chromatic passages use all pitches equally. See individual chord types for specific harmonic structures.

Key Signature

3 ♯ — The A key signature uses F♯, C♯, G♯.

A Chromatic Scale in Practice

The A Chromatic Scale uses the key signature of 3 sharps (F♯, C♯, G♯). A major has three sharps (F#, C#, G#) and a bright, clear sound. It is extremely common in popular music and rock, particularly on guitar, and is easily sung by most voices. On guitar, A positions offer open-string resonance for fingering positions for this scale.

The chromatic scale includes all 12 pitches within an octave, each a half step apart. It has no tonal center and is used as a reference for all other scales and as a compositional device. When played starting on A, the 12 notes are A, A♯, B, C, C♯, D, D♯, E, F, F♯, G, G♯. In this key the signature has 3 sharps (F♯, C♯, G♯). A is the universal tuning reference pitch (A440) and sits naturally on guitar, mandolin, and violin as an open string. Blues guitarists gravitate toward A because the open A string provides a driving bass note for shuffle rhythms and the standard blues box pattern sits comfortably in fifth position.

Tuning Frequencies Across Temperaments

Frequencies shown at A=440 Hz. View full temperament data for any note.

Related Scales

Guitar: A Chromatic Scale Positions

The A key offers 3 sharps (F♯, C♯, G♯) on guitar. Sharp-side keys like A are idiomatic guitar keys because open strings (E, A, D, G, B, E) align with the scale's natural resonance points.