Guinea pigs can grow to 25.4 centimeters long, or about 10 inches. At maturity, guinea pigs can weigh up to 1,100 grams, or about 39 ounces.
Guinea pigs are small animals native to South America that are now found around the world as pets and laboratory animals. They are also used as a source of food. Members of the rodent family, they are social and easy to handle. Modern guinea pigs are strictly domestic animals, but their closest wild relatives are important parts of the food chain in South America and are preyed on by coyotes, wolves, owls and hawks as well as by domestic dogs and cats.