A lot of people first notice a rodent problem through droppings.
That makes sense. You may never see the animal, especially if it is active at night, but the droppings are often left behind in places you can check. BPCA says droppings are a useful way to narrow identification down when you do not get a visual sighting.
The problem is that people often know they have found droppings, but not whether they point to rats or mice.
As a rule of thumb:
BPCA says typical mouse droppings are around 5 mm and pointed at both ends, while typical rat droppings are around 10 mm and pointed at both ends. It also says mouse droppings are often about the size and shape of a grain of rice, while rat droppings look like larger grains of rice and are pellet-shaped.
Mouse droppings are the smaller of the two.
BPCA describes them as often black and about the size and shape of a grain of rice. It also notes that each mouse can leave around 80 droppings per day, which is why they often show up repeatedly around cupboards, under sinks, and in roof spaces.
If the droppings are tiny and scattered around hidden indoor areas, mice are often the more likely culprit.
Rat droppings are more substantial.
BPCA says rat droppings are dark, pellet-shaped, and look like large grains of rice. It also says rats can leave up to 40 droppings in one night and that these droppings often appear clustered in certain areas.
So if the droppings are clearly larger and turning up in repeated spots, rats become a stronger possibility.
This part matters.
Droppings can help narrow things down, but they are not perfect on their own. BPCA’s own identification advice says droppings are a good tool for narrowing your search rather than acting like absolute proof in isolation.
That means you should also look at the wider pattern.
If you are trying to work out whether it is rats or mice, check for other signs too.
Useful clues include:
BPCA associates strong ammonia smell, nests, and damage to stored food with mice, while its rat guidance highlights grease marks, larger droppings, gnawing, and scratching or scuttling sounds.
Location gives context.
BPCA says mouse droppings are commonly found under sinks, around boilers, and in roof spaces, while its rat guidance points to clustered droppings, runs along walls, and signs around nesting areas such as wall voids, under floors, or garden structures.
So a few tiny droppings in a kitchen cupboard and larger pellets near a shed or along a run are not the same scenario.
Even if you are only trying to identify them, droppings are not something to treat like harmless dust.
CRRU UK guidance says rodents pose risks to health, hygiene, and food safety, partly because they can carry food-borne pathogens and contaminate areas where food is stored or prepared.
So use common sense. Identification is useful, but basic hygiene matters too.
If you are finding repeated droppings and you are still not sure whether they point to rats or mice, the good news is that you do not have to become an amateur detective to move forward.
Droppings are one clue, not the whole picture. Pest Gone can help you work out what the wider pattern suggests and whether it looks more like rat activity, mouse activity, or something else entirely.
