Rainbow bee-eaters are brilliantly coloured birds that grow to be 19–24 cm (max 28 cm) in length including the elongated tail feathers. The upper back and wings are green in colours. and the lower back and under-tail coverts are bright blue. The undersides of the wings and primary flight feathers are red and tipped with black, and the tail is black to deep violet. The rainbow bee-eaters
two central tail feathers are longer than the other tail feathers, and are longer in the male rainbow bee-eaters than in the females. The crown of the head, the stomach and breast, and the throat are pale yellowish in color, and the rainbow bee-eater has a black bib and a black stripe through its red eye.