Who has a longer tail—a mouse or a rat? - briefly
Rats generally possess longer tails than mice; a rat’s tail often matches or exceeds its body length, whereas a mouse’s tail is proportionally shorter.
Who has a longer tail—a mouse or a rat? - in detail
The tail of a rat exceeds that of a mouse in absolute length and in proportion to body size.
House mice (Mus musculus) typically have bodies 7–10 cm long. Their tails range from 5 cm to 9 cm, averaging about 80 % of the body length. Larger mouse species, such as the deer mouse (Peromyscus maniculatus), reach body lengths of 10–12 cm with tails of 8–10 cm, still short of one‑to‑one body‑tail ratios.
Norway rats (Rattus norvegicus) possess bodies of 20–25 cm. Tail lengths fall between 18 cm and 22 cm, often matching or slightly exceeding body length. Even smaller rat species, like the roof rat (Rattus rattus), have bodies of 15–20 cm and tails of 16–19 cm, maintaining a near‑equal length relationship.
Comparative data:
-
Mouse body length: 7–12 cm
-
Mouse tail length: 5–10 cm (≈ 70–90 % of body)
-
Rat body length: 15–25 cm
-
Rat tail length: 16–22 cm (≈ 95–100 % of body)
The longer absolute tail in rats results from both larger overall size and a tail that almost fully matches body length, whereas mouse tails remain proportionally shorter. Consequently, a rat consistently has the longer tail.