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Just as most male humans are taller than female humans, tomcats are typically larger than their daintier queen counterparts. However, this in no way means that all male cats are bigger than all female cats. Exceptions always do exist, and while some tomcats remain small, some queens grow very large.
Average Weight
For physically mature domestic male felines, the average weight is approximately 7 pounds, according to the Merck Veterinary Manual. Female felines are ever so slightly smaller than tomcats, and usually weigh in at around 6 pounds or so. These weights are by no means set in stone, however. Some male cats are rather lithe and weigh a lot less than overweight queens, for example.
Body Length
The average length of body also differs between male and female cats, according to Animal Bytes of SeaWorld. Feral male cats, which are biologically the same as typical household cats, usually are about 21 inches long. As for female cats, the body length is usually slightly shorter at around 19 inches. Tail length also differs subtly between the sexes, with male cat tails being roughly 11 inches long and female cat tails being just under 10 inches long.
Diet and Exercise
Without following a healthy diet and receiving sufficient exercise, a female cat can weigh significantly more than a male cat that has a similar body frame to her, even though tomcats usually are heavier than queens. If you have either a male or female cat and suspect a weight problem, schedule an appointment with the veterinarian pronto. Since healthy and acceptable weight ranges greatly among the different breeds, only a qualified professional will be able to tell you if your cat's size is conducive to well being and longevity.
Neutered Male Cats
Tomcats that are unneutered may grow to be bigger than fixed male cats that are neutered prior to attaining physical maturity. Male cats that never reach reproductive capability do not possess secondary sex traits, and because of that you may notice that their overall frames are significantly smaller than those of intact tomcats. Unfixed cats are usually more muscular, with fuller faces. However, this always, again, depends on the specific cat in question.