What's the average pet rat weight? The average weight for a male adult pet rat is about 450 to 650 grams (1-1.4 pounds) and for a female adult.
Male and Female Wistar and Sprague Dawley Rats from 3 to 12 Weeks held at ARC Average and Range of Weights (g) of Commonly Used Strains of Mice*.
Adult weight, Males 300-500g, Females 250-300g . The average daily consumption of feed and water for an adult rat is 15-25 g and 30-50 ml respectively.