Difference between Rats and Mice

As they both have small beady eyes, long tails, and similar coloring, rats and mice can be hard to differentiate from each other. Average fully grown mice weigh between 15 and 20 grams and measure up to 4 inches in length. Their thin and hairy tails generally exceed the total length of their bodies. Mice have small triangle-shaped snouts and ears that are relatively large compared to the rest of their body. Typically, the first sign of a mouse infestation is finding their rice-sized droppings around the home or garage. Additionally, individuals may notice greasy stains along walls or runways as mice have oils on their coats that leaves behind residue when they use the same path constantly.

In general, rats are much larger than mice, and the average adult weighs around 300 grams and grows between 8 and 10 inches long. Rats, too, have tails that just about double their total length, usually measuring 6 to 8 inches. However, unlike mice, their tails are thick and hairless. In addition, rats have small ears and blunted muzzles. Rat droppings can be distinguished from those of mice as they are considerably larger, approximately the size of baked beans. As all rodents must gnaw continuously to keep the size of their teeth manageable, it is difficult to tell which species may have caused damage around infested homes. However, rats are capable of causing slightly more damage due to their larger size.