The adult male Northern Pintail is between 23 to 30 inches (58.5 to 76 centimeters) in length and weighs 1 to 3 pounds (454 to 1362 Grams). Adult females measure 20 to 25 inches (51 to 63.5 centimeters) and weighs 1 to 2.5 pounds (454 to 1135 g). Males have a dark brown head and white breast with a white streak extending up the side of its head. From their back extending down and around their bellies, they have black and white speckled feathers with a yellow patch of feathers just above and behind their feet. Males also have a long, thin tail feather that can measure as much as 10 centimeters (4 inches) long. This feather narrows down to a sharp point and is where they get their name. The female has more of a drab, gray color to her feathers to help camouflage her as she sits on her nest, and her pin tail feather is only about one-quarter the length of the males.

These ducks have bluish-gray bills and they have longer necks than most other dabbling ducks, which makes them superb at feeding in deeper water.

Immature pintails measure from 53 to 68.5 centimeters (21 to 27 inches) and weigh 1 to 3 pounds (454 to 1362 g). Their feathers have more of a buff color to them; their bills are dark; and their heads range in color from dark brown to tan, while their bellies are speckled white and brown. Their tail feathers are dark, with cream colored edges and their feet are grayish green.

(Gooders, Boyer 1986; Soothill, Whitehead 1988; Bellrose 1980)

Range mass: 454 to 1362 g.

Range wingspan: 236 to 282 mm.