In music, alla breve [Italian: at the breve] (also sometimes called cut time or cut common time) refers to a musical meter notated by the time signature symbol (a broken circle with a line through it), which is the equivalent of 2/2.Alla breve is a "simple-duple meter with a half-note pulse". Common time, notated with the time signature symbol , is the equivalent of 4/4.

In contemporary usage alla breve suggests a fairly quick tempo. Thus, it is used frequently for military marches. From about 1600 to 1900 its usage with regard to tempo varied, so it cannot always be taken to mean a quick tempo.

Prior to 1600 the term alla breve derives from the system of mensural or proportional notation (also called proportio dupla) in which note values (and their graphical shapes) were related by the ratio 2:1. In this context it means that the tactus or metrical pulse (now commonly referred to as the "beat") is switched from its normal place on the whole note (semibreve) to the double whole note (breve).