They may bark when strangers arrive but are not suited to being guard dogs. They do, however, tend to attack cats that stray into their territory, unless they have been brought up living with a cat.
Unlike some other breeds, male whippets are as easy to housebreak as females. Male whippets are also as unaggressive as female whippets. Males are sometimes considered to be slightly more loyal and enjoy repetitive play. Females can be a little more complex and strong-willed. Males tend to be one to two inches taller and three to six pounds heavier than females.