The ioras are small to medium small sized passerines, ranging from 11.5 to 15.5 cm (4.5–6.1 in) in length. Overall the males are larger than the females. These are reminiscent of the bulbuls, but whereas that group tends to be drab in colouration, the ioras are more brightly coloured. The group exhibits sexual dimorphism in its plumage, with the males being brightly plumaged in yellows and greens. Unlike the leafbirds, ioras have thin legs, and their bills are proportionately longer. Calls are strident whistles songs are musical to human ears.