The common gull is a medium sized gull with a round head and small bill. Adult summer (breeding) plumage is predominantly grey above with white underparts. The body, head and tail is white and the mantle, the area immediately below the nape of the neck, is grey. The upper wing area is grey with the tips of the primary feathers coloured black. There is a large circular white spot partially superimposed over the black area. The trailing edge of the upper wings are marked with a narrow white stripe. Upper tail is white and the underwings are white tipped black. The short bill is a greenish yellow as are the legs and webbed feet. The iris is dark with a red orbital ring which is not apparent in winter plumage. Non breeding adults have grey brown markings over a white head extending to the top of the nape. Males and females are similar in appearance with the male being slightly larger than the female. Juvenile birds are mainly a grey brown colour with light brown upper wings and dark brown primaries. The upper tail is grey with a black band across the trailing edge. The bill is grey with a black tip and the legs vary from buff to pale pink.