The Indian Roller is a stocky bird about 26–27 cm long and can only be confused within its range with the migratory European Roller. The breast is brownish and not blue as in the European Roller. The crown and vent are blue. The primaries are deep purplish blue with a band of pale blue. The tail is sky blue with a terminal band of Prussian blue and the central feathers are dull green. The neck and throat are purplish lilac with white shaft streaks. The bare patch around the eye is ochre in colour. The three forward toes are united at the base.[2] Rollers have a long and compressed bill with a curved upper edge and a hooked tip. The nostril is long and exposed and there are long rictal bristles at base of the bill.[3][4]

Three subspecies are usually recognized. The nominate form is found from West Asia (Iraq, Arabia) to Bangladesh and north of the Vindhyas ranges. The subspecies indicus is found in peninsular India and Sri Lanka. The southern form has a darker reddish collar on the hind neck which is missing in the nominate form. The race affinis of northeastern India and Southeast Asia (Thailand, Yunnan, Indochina) is sometimes considered a full species, but within the Indian region, it is seen to intergrade with benghalensis. The form affinis is darker, larger and has a purplish brown and unstreaked face and breast.[2] It has the underwing coverts a deeper shade of blue.[3][5]