To sort animals by their weight, a moveable chute within an animal sorter is held at an elevated position by a counterbalance and rests upon rails which permit it to move to a lower position against the weight of the counterbalance when animals on the chute exceed the weight of the counterbalance. A single entrance permits animals to enter the chute while it is in the elevated position and pass through it to one exit if they are of a weight less than the weight of the counterbalance. The chute moves downwardly and laterally to its second position to be aligned with a second exit if the animal is heavier than the counterbalance.