The gadwall is 47–58 cm (19–23 in) long with a 78–85 cm (31–33 in) wingspan. The male is slightly larger than the female, weighing on average 990 g (35 oz) against her 850 g (30 oz). The breeding male is patterned grey, with a black rear end, light chestnut wings, and a brilliant white speculum, obvious in flight or at rest. In non-breeding (eclipse) plumage, the drake looks more like the female, but retains the male wing pattern, and is usually greyer above and has less orange on the bill.