The Sonata for Two Pianos in D major, K. 448 (375a), is a work composed by Wolfgang Amadeus Mozart in 1781, when he was 25.

It is written in sonata-allegro form, with three movements.

The sonata was composed for a performance he would give with fellow pianist Josepha Auernhammer.

[1] Mozart composed this in the galant style, with interlocking melodies and simultaneous cadences.

The sonata is written in three movements: Mozart's K 448 was the composition used in the original study that led to the theory of the so-called Mozart effect, which posited that listening to the piano sonata improved spatial reasoning skills, later widened in pop-science to an increase in IQ in general.