Duck vs Goose

Ducks and geese are both waterfowl with webbed feet and broad, flat bills, so the family resemblance is strong. The easiest split is overall build. Geese are larger and longer-necked, and the skeleton backs it up: ducks have 16 or fewer neck bones, while geese and swans have 17 to 24.

This page uses the two birds most people see in parks, the mallard and the Canada goose, as the benchmark. There are many more kinds of ducks and geese, and some small geese or big ducks sit near the middle, so use the whole set of cues rather than a single one.

Duck vs Goose side by side

Last verified October 2026. Typical values; individual animals, products and local prices vary.

When you are looking at which

Duck

• The bird is about 2 to 3 pounds, roughly 20 to 26 inches long, and has a short neck.
• The male has a glossy green head and a yellow bill, or the bird is mottled brown.
• It tips headfirst into the water and holds its tail high while it feeds.
• It mingles with other ducks on a city pond and is easy to approach.

Goose

• The bird is over 2.5 feet long with a long neck held upright.
• It has a black head and neck with a white chinstrap and a tan breast.
• It grazes on a lawn or field as well as on the water.
• It travels in flocks, often flying in a V formation.

How this works

The quiz asks five questions: size, neck, head color, feeding and weight. They use published size data, a skeleton fact about neck bones, and and identification notes for the mallard and Canada goose, the two most familiar waterfowl in North America.

It can mislead with unusual birds. Diving ducks, muscovies, swans and small geese such as the cackling goose do not follow the mallard and Canada goose numbers exactly. If your bird does not fit either description, a field guide or local birding group can help.

Where these numbers come from

The figures and defaults on this page are based on:

• Cornell Lab of Ornithology: Mallard Identification, Mallard size, weight, plumage and dabbling behavior (checked October 2026)
• Cornell Lab of Ornithology: Canada Goose Identification, Canada goose size, weight, plumage, grazing and V flocks (checked October 2026)
• Reconnect with Nature: What's the difference? Ducks vs. geese, Neck-bone counts and the general duck versus goose neck difference (checked October 2026)

Field-identification guide using the mallard and Canada goose as benchmarks; other duck and goose species differ.