A quick-adjustable animal collar includes a buckle including a female buckle member and a male buckle member releasably engaged with each other and including a strap adjusting structure. At least one strap is attached to the buckle. The at least one strap extends between the female and male buckle members. The at least one strap includes a first length slidable through the strap adjusting structure in a non-overlapped manner and having a free end. The size of the quick-adjustable animal collar changes with adjusting the first length of the at least one strap, with the first length of the at least one strap including an increased extent disposed within a circumference of the quick-adjustable animal collar as the size of the quick-adjustable animal collar is reduced.
