Dog Breed Size Guide

Puppy & Adult Collar Sizing

Choosing the right collar size can feel tricky - especially for growing puppies. This guide gives a general idea of expected neck sizes for popular dog breeds at both puppy and adult stages, helping you choose a collar with enough adjustment room to grow comfortably with your dog.

Every dog is individual, so these measurements are intended as a guide only. For the best fit, we always recommend measuring your own dog before ordering.

How to Measure Your Dog

Use a soft measuring tape around the middle of your dog's neck where the collar will naturally sit. The measurement should be snug but not tight - close enough that the collar will sit securely without slipping over the head, while still remaining comfortable for your dog.

For puppies, we recommend measuring regularly while they are growing, as they can change size surprisingly quickly during the first few months.

For a more detailed step-by-step guide, including where to measure for different collar styles and common measuring mistakes to avoid, please see our full Dog Measurement Guide.

Puppy vs Adult Collar Sizing

Many puppies grow quickly in height and weight during the first year, but neck growth tends to slow earlier than people expect. In many breeds, by around 6-8 months old the neck circumference is already close to adult size, even though the dog may continue filling out afterwards.

Because our collars are custom made with multiple adjustment holes, many puppies can wear the same collar through to adulthood when sized appropriately.


Small Breeds

Breed Puppy
Neck Size
Adult
Female
Adult
Male
Chihuahua 15-20cm 18-25cm 20-28cm
Miniature Dachshund 18-24cm 22-30cm 25-33cm
Toy Poodle 15-22cm 20-28cm 22-30cm
Cavalier King Charles Spaniel 18-24cm 25-33cm 28-38cm
French Bulldog 20-28cm 30-40cm 35-45cm
Pug 18-26cm 30-38cm 34-42cm
Jack Russell Terrier 18-24cm 25-32cm 28-36cm

Medium Breeds

Breed Puppy
Neck Size
Adult
Female
Adult
Male
Border Collie 22-30cm 32-42cm 38-48cm
English Springer Spaniel 22-30cm 35-45cm 40-50cm
Staffy 22-30cm 35-45cm 40-50cm
Whippet 20-28cm 28-38cm 32-42cm
Vizsla 24-32cm 35-45cm 40-50cm
Australian Shepherd 24-32cm 35-45cm 40-50cm

Large Breeds

Breed Puppy
Neck Size
Adult
Female
Adult
Male
Labrador Retriever 24-34cm 40-50cm 45-55cm
Golden Retriever 24-34cm 40-50cm 45-55cm
German Shepherd 24-34cm 40-50cm 45-58cm
Boxer 24-34cm 38-48cm 42-55cm
Dobermann 24-34cm 38-48cm 42-55cm
Standard Poodle 24-34cm 35-45cm 40-50cm
Weimaraner 24-34cm 38-48cm 42-52cm

Giant Breeds

Breed Puppy
Neck Size
Adult
Female
Adult
Male
Rottweiler 28-38cm 45-58cm 50-65cm
Great Dane 30-40cm 45-60cm 55-70cm
Newfoundland 30-40cm 48-62cm 55-72cm
Bullmastiff 30-40cm 45-60cm 55-70cm
Saint Bernard 30-40cm 50-65cm 58-75cm

A Few Important Notes

  • Mixed breed dogs can vary significantly and may not fit neatly within breed averages.
  • Sighthounds (such as Whippets and Greyhounds) often need a different collar shape due to their narrower heads and larger necks.
  • Fluffy-coated breeds can appear larger than their actual neck measurement.
  • Young puppies should always be checked regularly to ensure collars are not becoming too tight as they grow.

If you're unsure which size will suit your dog best, feel free to get in touch with your dog's breed, age, weight, and neck measurement and we’ll happily help guide you.