|Relative key||F♯ minor|
|Parallel key||A minor|
|Dominant key||E major|
|A, B, C♯, D, E, F♯, G♯, A|
In the treble, alto, and bass clefs, the G♯ in the key signature is placed higher than C♯. However, in the tenor clef, it would require a ledger line and so G♯ is placed lower than C♯.
Although not as rare in the symphonic literature as sharper keys, examples of symphonies in A major are not as numerous as for D major or G major. Beethoven's Symphony No. 7, Bruckner's Symphony No. 6 and Mendelssohn's Symphony No. 4 comprise a nearly complete list of symphonies in this key in the Romantic era. Mozart's Clarinet Concerto and Clarinet Quintet are both in A major, and generally Mozart was more likely to use clarinets in A major than in any other key besides E-flat major. Moreover, the climax part of Tchaikovsky's Violin Concerto (Tchaikovsky) is also A major.
A major is often thought of as the simplest key for violin and other orchestra instruments and beginning violin students' first pieces are usually simple ones in this key.
A major occurs frequently in chamber music. Franz Schubert's Piano Quintet known as the Trout Quintet and Antonín Dvořák's Piano Quintet No. 2 are both in A major. Johannes Brahms, César Franck, and Gabriel Fauré wrote violin sonatas in A major. In connection to Beethoven's Kreutzer Sonata, Peter Cropper said that A major "is the fullest sounding key for the violin."
According to Christian Friedrich Daniel Schubart, A major is a key suitable for "declarations of innocent love, ... hope of seeing one's beloved again when parting; youthful cheerfulness and trust in God."
For orchestral works in A major, the timpani are typically set to A and E a fifth apart, rather than a fourth apart as for most other keys. Hector Berlioz complained about the custom of his day in which timpani tuned to A and E a fifth apart were notated C and G a fourth apart, a custom which survived as late as the music of Franz Berwald.
Notable compositions in A major
- Violin Concerto No. 5 in A major, K. 219 – Wolfgang Amadeus Mozart
- Symphony No. 29 in A Major, K. 201 – Wolfgang Amadeus Mozart
- Piano Concerto No. 23 in A major, K. 488 – Wolfgang Amadeus Mozart
- Clarinet Concerto in A major, K. 622 – Wolfgang Amadeus Mozart
- Symphony No. 7 in A major, Op. 92 – Ludwig van Beethoven
- Piano Sonata No. 2 Op. 2/2 – Ludwig van Beethoven
- Piano Sonata No. 28 Op. 101 – Ludwig van Beethoven
- Violin Sonata No. 6 Op. 30/1 – Ludwig van Beethoven
- Violin Sonata No. 9, Op. 47 – Ludwig van Beethoven
- String quartet No. 5, Op. 18/5 – Ludwig van Beethoven
- Trout Quintet – Franz Schubert
- Piano Sonata in A major, D 664 – Franz Schubert
- Polonaise, Op. 40/1 "Military" – Frédéric Chopin
- Symphony No. 4 in A major, Op. 90 "Italian" – Felix Mendelssohn
- Piano Concerto No. 2 in A major, S.125 – Franz Liszt
- Serenade No. 2 Op. 16 – Johannes Brahms
- Violin Sonata No. 2 in A major "Thun", Op. 100 – Johannes Brahms
- Piano Quartet No. 2, Op. 26 – Johannes Brahms
- Violin Sonata – César Franck
- Symphony No. 6 in A major – Anton Bruckner
- Piano Sonata No. 6 in A major, Op. 82 – Sergei Prokofiev
- String Quartet No. 2 in A major, Op. 68 – Dmitri Shostakovich
- Symphony No. 15 in A major, Op. 141 – Dmitri Shostakovich
- Mark Anson-Cartwright (2000). "Chromatic Features of E♭-Major Works of the Classical Period". Music Theory Spectrum. 22 (2): 178. JSTOR 745959.
- Peter Cropper, "Beethoven's Violin Sonata in A major, Op.47 'Kreutzer': First Movement", The Strad, March 2009, p. 64
- Rita Steblin (1996) A History of Key Characteristics in the Eighteenth and Early Nineteenth Centuries, University of Rochester Press, p. 123, ISBN 0835714187.
- N. D. Mar (1981). Anatomy of the Orchestra University of California Press, p. 349, ISBN 0520045009.
- Colin Lawson, Mozart: Clarinet Concerto, A Cambridge Music Handbook, Cambridge University Press, 1996.
- Media related to A major at Wikimedia Commons
|The table indicates the number of sharps or flats in each scale. Minor scales are written in lower case.|