Rats and mice have become common pets in recent times. Apparently, they may look like the same, but there are a lot of differences among them. In this article, we will cover all the major and minor differences between a rat and a mouse. This article will enable you to select a rat or a mouse as a pet based on their differences.

Rats vs. Mice

The word “rat” is used to describe medium-sized rodents. Kangaroo rats, cotton rats, Norway rats, and black rats are the most common species of rodents called as rats. On the contrary, mice are identified as tiny, sparrow-sized rodents. House mice, field mice, and deer mice are the most commonly known rodents labeled as mice. Both rats and mice have tiny long thin tails.

Both rats and mice are social animals and interact with humans easily. They like to stay in groups. It is better to keep same-sex animals in one cage so that you do not have to deal with a large number of children.

Physical Differences

Mice are smaller in size as compared to rats. A baby rat is just about the same size as a full grown healthy mouse. Mice can grow 12-20 centimeters in length and have a weight of around 30 grams; rats can grow to 40 centimeters in length and can weigh around 650 grams. Mice have ears that are large and floppy while rats have smaller ears. The head of mice is triangular and small as compared to rats. Mice’s eyes are big relative to their head size and rats have small eyes as compared to their head-size.

Relationship with Humans

When it comes to the relationship with humans, both the pets develop a very good relationship with their owners. Rats like to stay out of their cage and once they are acquainted with you, you can cuddle them, place them on your hands and knees while you relax on the couch. Male rats are more stable and would sit for longer periods of time when out of the cage. Female rats, on the other hand, will try to wander here and there when they are allowed to leave their cage. Rats need at least an hour out of their cage on daily basis.

Mice are generally much happy when they are inside their cage. They will play with their fellow dwellers and amuse you with their cute tricks. They are happy to stay inside their cage if there is ample space for them to play around.


There is not much difference when it comes to their housing. Cage size and accessories are almost the same. However, if you plan to keep your mice inside the cage for more than a day or two, you should house them in a larger cage as compared to rats.


Rats would need a little human diet as complimentary treats. They love to eat regular human diets. Apart from this, both rats and mice can enjoy processed diet, a little supply of fresh fruits and vegetables and occasional treats of baked chicken, eggs and nuts.


When it comes to being hygienic and staying clean, rats are on the advantage. They have a less bad odor as compared to mice. Their droppings also make less of a mess and cleaning them is easy. Pet rats can also be toilet-trained while pet mice can never learn to do toilet at a specific space in their cage.

Poop Patterns

When it comes to poop patterns, it is very easy to tell the difference between them. They are of different sizes. Mouse excrete poop that looks like a small grain of rice and has pointy ends. On the contrary, a rat’s pellet is much bigger than a mouse’s. It looks like twenty times bigger than mouse’s and is rounder. The color of both is brown and is harmful to human health. It is recommended that you wear hand gloves and face mask while cleaning their cages.

Daily Routine

Generally, all the pets belonging to the rodent family are nocturnal. Mice do not change their routine no matter what. Mice, on the other hand, can adjust their sleeping pattern gradually and will start to stay up during the daytime.

Birth Patterns

A female mouse can give birth 4-12 pups in each of the 6-10 litters in one year whereas a female rat can give birth to 7-8 pups in 4-6 litters during a single year.


When kept as pets, both mice and rats can live up to 3 years. When in the open they do not survive for more than a year.


While it is true that both rats and mice are adorable pets. We wanted you to get first-hand knowledge of all their habits and lifestyle, so you can make the best decision to get a pet for you and your family.


Please enter your comment!
Please enter your name here