Collar size guidelines

Small dogs
Neck 12-16 inches
Chest 18-24 inches
Weight 18-25 pounds
Breeds: Basenji, Beagle, Border Collie, many Terriers, Cocker Spaniel, Corgi, Keeshond, Samoyed, Schipperke

Medium dogs
Neck 14-18 inches
Chest 24-28 inches
Weight 20-65 pounds
Breeds: Australian Shepherd, Standard Dachshund, Sheltie, American Staffordshire Terrier, Bull Terrier, Char-Pei, most Pointers, Coon Hound, Standard Schnauzer, most Spaniels

Large dogs
Neck 16-20 inches
Chest 28-32 inches
60-85 pounds
Breeds: Afghan Hound, most Collies, Doberman Pinscher, English Bulldog, German Shepherd, Greyhound, most Retrievers, most Setters, Siberian Husky, Weimaraner

Extra-large dogs
Neck 18-28 inches
Chest 32-36 inches
Weight 80-150 pounds
Breeds: Alaskan Malamute, Bernese Mountain Dog, Boxer, Great Dane, most Mastiffs, Irish Wolfhound, Rottweiler

Supersize dogs
Neck 26-34 inches
Chest 36-44 inches
Weight 140-250 pounds
Breeds: Larger Mastiffs, Great Pyrenees, Newfoundland, St. Bernard