Chorus frogs are among the smallest frogs in Canada (rivalled by the spring peeper). Adults grow to about 3.5 cm (1.5 in.) in length.
Male chorus frogs have a rasping breeding call that sounds like a thumbnail repeatedly drawn over the teeth of a pocket comb, and is often assumed to come from a much larger frog. Breeding choruses early in the season can be heard on clear, sunny days, but shift to evenings or cloudy, rainy days as the season progresses.
A pattern of longitudinal stripes, spots, or both, marks the back and sides. Of the seven species of chorus frogs living in North America, one is found in Canada. The chorus frogs occurring in southern Quebec and southern Ontario are brown, but those of northwestern Ontario to the Peace River district of British Columbia are frequently green or red.
In Canada, chorus frogs generally inhabit meadows, fields, and clearings in the east and north but are most abundant on the southern prairies of central Canada. Although chorus frogs belong to the tree frog family, their toe discs are minute, and they rarely climb above the tops of tall grasses.