Their wingspan is 40–55 mm. The upper side of the wings is dominantly cherry red. There is an eye-shaped spot in white, blue, and black at the top of each wing. The bottom sides of the wings are dark grey to black. During flight, they are easily noticeable because of the bright colours of the upper side of their wings. Their eggs, caterpillars, chrysalides, and imagoes are an important link in the food chain of ecosystems, as they are food for many invertebrates and vertebrates. The imagoes of butterflies require nectar for survival, making them important pollinators. In Tallinn, they are most common in Astangu, Pääsküla bog, Raku, Liiva, and Merimetsa. In Rocca al Mare, the peacock butterfly is one of the most common butterflies in addition to the green-veined white butterfly and the Essex skipper.