Adults of this large swan typically range from 140 to 160 cm. long, although can range in extreme cases from 125 to 170 cm. with a 200 to 240 cm. wingspan. Males are larger than females and have a larger knob on their bill. The mute swan is one of the heaviest flying birds. In several studies from Great Britain, males (known as cobs) were found to average from about 10.6 to 11.87 kg., with a weight range of 9.2–14.3 kg. while the slightly smaller females (known as pens) averaged about 8.5 to 9.67 kg., with a weight range of 7.6–10.6 kg

.All mute swans are white at maturity. Mute swans nest on large mounds that they build with waterside vegetation in shallow water on islands in the middle or at the very edge of a lake.

The mute swan is less vocal than the noisy whooper and Bewick's swans; they do, however, make a variety of grunting, hoarse whistling, and snorting noises, especially in communicating with their cygnets, and usually hiss at competitors or intruders trying to enter their territory.

It is the beautiful decoration for park and ponds.