Identify Rodent Droppings

Mouse Droppings vs Rat Droppings

Homeowners may mistake house mouse droppings for rat waste, as both rodents defecate on the move. Likewise, both pests’ poop is dark in color and usually only a few inches off from the other. For example, Norway rat droppings are about three fourths of an inch long, while roof rat pellets are approximately one half of an inch in length.

Without proper measurement, differentiating between the two may be challenging. That being said, homeowners can rely on location to help with identification. This is because house mice thrive in many areas around the home, while roof rats are typically only found in attics and on roofs. Additionally, Norway rats are seldom indoors unless in the basement.

Mouse Droppings

What Does Mouse Poop Look Like?

mouse feces
Mouse droppings
house mouse poop
house mouse droppings


mice feces
mice feces

Mouse droppings are small pellets about a quarter of an inch long with pointed ends. The pellets are generally dark brown or black, though the color may vary depending on individual mouse diets.  Mouse droppings typically look like grains of dirty rice.

Most droppings taper at both ends and harden the longer they sit.

Most droppings from house mice, deer mice, and white-footed mice share characteristics and become hard and dry after a few hours. The amount and frequency of new pellets can often be used to determine the size of mouse infestations.

Where Do You Find Mouse Poop?

Mice tend to invade homes once the weather cools and in search of new food sources. Once mice find places to nest indoors, homeowners may begin to notice fecal matter in areas the rodents frequent.

Homeowners frequently find mouse droppings in areas of high pest traffic. Mice may deposit as many as 75 to 80 droppings a day as the rodent explores the environment in search of food. Mouse droppings are often found along baseboards, near cardboard boxes, or on any other accessible surface near a food or nesting source.

As timid creatures, mice typically keep away from open spaces, making it possible for droppings to be found during renovations or construction, as the rodents may take up residence in house walls or insulation. In cases of serious invasion, it may become necessary to contact local pest controllers to eradicate the issue, as home traps may become expensive and less effective.

Rat Droppings

What Does Rat Poop Look Like?

norway rat poop
norway rat droppings


roof rat poop
roof rat droppings


The rats most commonly found infesting homes are Norway and roof rats. The feces of these species is often used by exterminators as a way to identify which type of rat is present.

Rat droppings are at least twice the size of mouse droppings, and Norway rat feces is typically larger than those of roof rats. Norway rat droppings measure 3/4 of an inch in length and 1/4 of an inch in diameter. They are rectangular in shape and have blunt ends. Roof rat droppings are an average length of 1/2 of an inch and share the same diameter as those of Norway rats. They are sausage-shaped with pointed ends. All rat feces appears brown to black and usually contains as many as 200 hair fragments.

Where Do You Find Rat Poop?

Rats leave behind an average of 40 to 60 droppings each day. As such, infested homes are often littered with feces. Rats most often expel their waste in corners and secured areas, and their droppings may be found in and around pet food dishes, food storage containers, recycling bins, cabinets, drawers, counters, and under sinks.

Rodents Droppings & Disease

Disease can be transmitted by rodent feces in three ways:

  • the inhalation of dropping dust and particles
  • direct contact with infected droppings
  • the consumption of food that has been contaminated by droppings

Humans may contract Hantavirus Pulmonary Syndrome, hemorrhagic fever with renal syndrome, Lassa fever, rat-bite fever, salmonellosis, and tularemia by coming into contact with rat feces.

Individuals sanitizing homes after infestations should never sweep or vacuum up droppings so as to avoid stirring up dust and particles.

Rat Infestations