How Tight Should a Dog Collar Be? More About Collar Sizes

A dog collar is an accessory that pet owners use for dog training purposes or for control by attaching a lead or leash to the collar. There are many types of dog collars, though the most commonly used kind of dog collar is the buckle collar, which fastens around the dog’s neck with a clasp or buckle. It also has a metal loop, called an O ring or D ring, to which dog owners connect their leashes and identification tags, including vaccination records.

There are several types of dog collars, including the:

• Buckle collar: This kind of collar has a clasp or buckle that buckles around your pet’s neck. With the O ring or D ring, a metal loop, dog owners connect their leashes.
• Harnesses: These circle the dog’s chest and torso. Harnesses are useful for dogs that pull on their leash or for small breed dogs like Pomeranians or Maltese, which often have problems with their necks or tracheas when using a traditional collar.
• Head collars: Halters—another name for head collars—fasten around the dog’s head to redirect the dog when unwanted behavior occurs.
• Martingale collar: Use this type, also known as a greyhound collar, for dogs that slip out of their collar while walking on a leash.
• Slip collar: This type of collar trades a traditional clasp or buckle for a circular loop on one end that slips over your pet’s neck.

There are five different dog collars sizes. The following is a dog collar sizing chart and the appropriate dog breeds for each size:

1. 1. Extra small: The collar length for extra small collars is between six and eleven inches, while the collar width is less than one inch (0.56 inches). Extra small collars are best for small breed dogs like Yorkshire terriers, chihuahuas, and toy and teacup poodles.
2. 2. Small: The next size up for dog collars, small collars, measures between eleven and thirteen inches in length, but retains the small width of extra small collars (0.56 inches). A small collar fits various small terriers, including Boston terriers and Jack Russell terriers, as well as beagles, French bulldogs, and pugs.
3. 3. Medium: A wide size range of dog breeds use the medium collar size, which measures between thirteen and nineteen inches in length and 0.75 inches in width. Medium collars are the right size for dogs ranging in build from basset hounds and bichon frise to border collies, pit bull terriers, and standard schnauzers. Miniature schnauzers and Scottish terriers wear small and large collars, respectively.
4. 4. Large: Bigger dog breeds—such as Dobermans, dalmatians, golden retrievers and Labrador retrievers, German shepherds, and Irish setters—need large dog collars. These reach almost two feet in length—collars for large dogs measure between eighteen and twenty-three inches—and nearly an inch (0.94 inches) in width.
5. 5. Extra-large: Dogs that exceed seventy-five pounds in weight need extra-large collars. These include Great Danes, mastiffs, and rottweilers, and their collars measure between twenty-four and thirty inches in length and between one and two inches in width.

There are several ways to measure your dog’s collar size. They include:

• Use a measuring tape. Wrap a flexible or soft tape measure around the circumference of your dog’s neck. Loop the tape around the dog’s neck above the shoulder blades or approximately three to five inches below their jawline. You can also use a piece of string if measuring tape isn’t available.
• Make the loop snug. Take the end of the measuring tape and overlap the rest of the loop around the dog’s neck. The loop should be snug but not tight. Examine the tape to determine the correct neck measurement of your dog.
• Add inches. Make note of your dog’s neck size and then add one to two inches to that number. The perfect fit for your dog is a snug-fitting collar but not a tight collar.
• Use their current collar. If your dog is fully grown, you can use its current collar to determine the size for a new collar. Remove their collar and lay it flat, and then measure the flat collar from the buckle to the sizing hole that is currently in use.

You can determine how tight a dog’s collar should be with the “two-finger rule.” Slip the two middle fingers on your hand under the dog’s collar. If your fingers slide under the collar but also remain snug, the collar is the proper fit. If you have to force your fingers under the collar, it’s too tight, and if there’s no snug feeling at all, your dog needs a tighter collar.

A dog’s collar should be tight enough to fit snugly around its neck but also allow for breathing room. The right collar is not a loose collar that slips off your dog’s neck when you pull the leash, and it’s not so tight that it causes skin irritation and, in extreme cases, strangulation.

Dogs should always wear a pet collar when they are outside. Collars help pet owners locate dogs if they become lost. However, you can remove a dog’s collar at bedtime, or if they sleep in a crate in order to avoid the D-ring or ID tags catching on the metal parts of the cart. Additionally, dogs often catch their paws or legs on other dogs' collars during play. Make sure you fully enclose any play spaces if you remove your dog’s collar.

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