The Difference Between Rat and Mouse

“Oh no, we have a rat in the house!”

“No dear, it’s just a mouse!”

But what is the difference? Both are rodents. Both can damage your house, chewing through walls and cords and destroying food stores. Both can carry disease and germs. In short, both can be a pest if they infiltrate your homes. Both are also very smart, much smarter than most people can imagine. They also make great pets when domesticated. But there are differences between rats and mice, other than the obvious size differences?


Rats are generally larger than mice and they very often have meaner dispositions. Rats have been known to attack people and even kill babies in their cribs in urban areas. There are black versions of a rat and brown versions. Here are some characteristics of a typical rat:

• 6-16” in length (with tail)
• Can weigh from a third of a pound to a pound
• No hair on their tails
• Large feet and large ears

Brown Rats

• Tend to be on the larger side
• Tail is shorter than length of the body
• Blunt nose
• Tend to be thicker or fatter

Black Rats

• Smaller and thinner
• Tail is longer than length of the body
• Pointy nose


Mice tend to be more docile than rats, though they too can be aggressive. They are generally much smaller than rats, although it can be difficult to discern the difference between baby rats and full grown mice. Here are some characteristics of mice:

• 1” to 4” in length (with tail)
• Very light, weighing less than a ¼ of a pound
• Long, thin, hairy tails
• Large ears and short hair

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