When during a baseball game are fans encouraged to "stretch"?

Fans are encouraged to stretch during the seventh inning, in a tradition known as the seventh-inning stretch.

It takes place between the two halves of the inning, when spectators commonly stand, move around, and stretch their arms and legs. The break also gives players a brief pause during the late stages of the game.

Many ballparks pair the tradition with a crowd singalong of “Take Me Out to the Ball Game.” Although the custom’s exact origin is uncertain, it became especially popular through baseball broadcasters, including Harry Caray. The song itself was written in 1908 by Jack Norworth and Albert Von Tilzer, neither of whom had attended a baseball game before writing it.

The seventh-inning answer applies to standard professional baseball. Shorter games can use a different convention: softball and some seven-inning games may have a fifth-inning stretch instead.