The first piano concerto after settling in Vienna. Among Concertos Nos. 11-13, composed in quick succession from late 1782 to the following year, No. 12 is believed to have been created first. Its premiere took place at the subscription concerts of that season.

According to Mozart's letter from this period (December 28, 1782), his piano concertos were composed to be "neither too difficult nor too easy, satisfying not only connoisseurs but also those who are not, for some reason." True to his words, the three piano concertos from this period have a simple structure, are pleasing to the ear, and possess rich content. They also share the common feature of being arranged so that they can be performed with a string quartet accompaniment, without wind instruments. The instrumentation for this No. 12 is small, consisting of solo piano, two oboes, two horns, and strings (four parts).

As a social and brilliant genre, the piano concerto was an effective repertoire for Mozart's concerts. Furthermore, by allowing him to showcase both his compositional and performance skills, it likely played a significant role in establishing Mozart's reputation in Vienna. Subsequently, the number of his piano concertos would increase with his rising popularity, and this work can be considered a catalyst for that trend.

Two types of cadenzas by Mozart himself are preserved for each movement, and two types of Eingänge are also preserved for the second movement.

First Movement: Allegro, A major, 4/4 time.

Concerto-sonata form. A movement characterized by brightness, expansiveness, and brilliance, befitting his debut in Viennese society. The piano plays a leading and active role throughout the movement.

Second Movement: Andante, D major, 3/4 time.

Small-scale concerto-sonata form. The second theme, following the lyrical first theme, bears a resemblance to the first theme of the previous movement. It is interesting that it is placed in a position where the key is also A major, the same as the first movement's tonic key.

Third Movement: Rondo. Allegretto, A major, 2/4 time.

Rondo form. This is an approachable movement because the same material appears repeatedly; for example, material from the lighthearted rondo theme is incorporated into the episodes, and the two episodes are related to each other.