Dog Coat Sizing by Breed | Measure, Don’t Guess

For the full breakdown, see our best Dog Coats guide.

Most dog owners pick a coat by breed name, then discover it’s too tight across the chest or too long in the back. The reason is simple: there is no industry standard. A breed like a Labrador can span multiple sizes depending on sex, build, and individual proportions, so a breed chart is only a rough starting point.

The reliable route is a tape measure. Take two or three key measurements, compare them against the specific brand’s chart, and you’ll get a coat that actually fits. Below is how to measure, what the breed examples really mean, and where sizing goes wrong.

How To Measure Your Dog For A Coat

You only need a flexible tape measure and a cooperative dog. Measure twice, buy once.

1. Back length: Measure from the base of the collar (where the neck meets the shoulders) to the base of the tail. This is the single most important number for most coats.
2. Chest girth: Wrap the tape around the widest part of the chest, just behind the front legs. Keep it snug but not tight.
3. Neck girth: Measure around the base of the neck where the collar sits, leaving room for two fingers.

Some brand charts also ask for tummy depth or weight. The guides from Shires, Doggie Coats, and Chaar all agree on the core principle: match your measurements to that brand’s size band, and treat breed names as a guide only.

When you’re between sizes, the chart’s fit guidance wins. Most brands recommend sizing up for deep-chested or long-bodied dogs, since a coat that fits lengthwise can still fail at the chest or neck. If your dog is a Greyhound, Whippet, or Dachshund, expect to size up from what weight charts suggest.

What Breed-Based Size Charts Actually Show

Breed charts are helpful for narrowing down your starting point, but they conflict with each other. The same breed can land in different sizes depending on which chart you read.

Notice how the breed examples shift between the two brands. Shires lists a Corgi at 45 cm back length (size S), while Doggie Coats places the same breed in the M band. Neither is wrong — they just use different breed-average assumptions.

Chaar’s chart takes a different approach, tying sizes to both back length and chest girth. Their size 1 fits a Chihuahua at 20 cm back length and 26–30 cm chest, while their size 4 fits a Pug or Jack Russell at 33 cm back and 40–46 cm chest. Their largest standard size, 7, fits Labradors at 50 cm back and 64–72 cm chest. Beyond that, sizes 8–13 are reserved for their Fortress and Oilskin coat lines only.

Where Dog Coat Sizing Goes Wrong

The most common mistake is trusting breed alone. A working Labrador and a pet Labrador can differ by several centimeters of back length, and a deep-chested breed like a Bulldog needs more room at the chest than a length measurement suggests.

Unit confusion is another trap. Some charts use centimeters, others inches, and a few mix in weight ranges. Doggie Coats’ measuring guide uses centimeters throughout; Shires does too. If you measure in inches, convert carefully before comparing.

Fit compatibility matters just as much as size. A coat can fit perfectly along the back but pull tight across the chest or ride up at the neck. For barrel-chested or deep-chested dogs, look for coats with adjustable chest straps or gussets, and size up when in doubt. It’s easier to take in a slightly loose coat than to stretch one that’s too small.

If you’re ready to skip the guesswork entirely, our tested roundup of the best dog coats compares fit, coverage, and durability across the sizes that matter for your dog.

FAQs

Should I size up for a fluffy or long-haired dog?

Usually, yes. A thick coat adds bulk that changes how a measured back length sits on the body. If your dog has a heavy double coat, measure over the fur as it naturally lies, then size up if you’re between bands. A snug coat compresses the fur and reduces warmth.

Do puppy coats use the same size chart as adult dog coats?

No. Puppies grow quickly, and most brand charts assume adult proportions. Buy a puppy-sized coat based on current measurements, then expect to replace it within a season. Stretchy or adjustable coats with velcro straps extend that window by a few weeks.

My dog measures in between two sizes — which should I pick?

Pick the larger size if your dog is deep-chested, broad-shouldered, or long-bodied. Pick the smaller size only if the chart’s fit notes explicitly recommend it for your dog’s build. A slightly loose coat stays warmer than one that restricts movement at the shoulders.