Rat droppings are small, dark pellets found in areas where rats have been active. Rats generally produce 40-100 droppings per day. So, if you’re finding more than that, you probably have more than one rat. Second, look at the size of the droppings. If they’re small, you likely have young rats; if they’re large, you likely have adult rats. Finally, take a look at where you’re finding the droppings. If they’re concentrated in one area, you likely have a nest of rats; if they’re spread out, you’re likely to have rats traveling throughout your home. By taking these factors into account, you can get a pretty good idea of how many rats you have in your home.