How to measure your dog for a collar
Measure the dog in front of you, not the breed name on the size chart.
A well-fitting dog collar should sit securely without feeling tight, and it should not be loose enough to slip over your dog’s head. The most reliable starting point is your dog’s actual neck measurement.
How to measure your dog for a collar
- Use a soft fabric measuring tape.
- Measure around the part of the neck where the collar normally sits.
- Keep the tape close to the coat without pulling it tight.
- Record the measurement in centimetres and compare it with the size range shown on the exact product page.
Do not choose by breed alone. Two dogs of the same breed can need different collar sizes.
How tight should a dog collar be?
As a general comfort check, you should be able to slide two fingers between the collar and your dog’s neck. Blue Cross and the Kennel Club both use this as guidance for a correctly fitting collar.
The collar should still be secure enough that it cannot easily pass back over the dog’s head. Check the fit again after adjusting the buckle.
What if the measurement sits between two sizes?
Choose a size that places your dog’s neck measurement comfortably inside the stated adjustment range rather than right at its extreme. This gives you useful adjustment in either direction.
If the product uses numbered sizes, compare your measured neck circumference with the individual size range shown on that product page.
How often should you recheck the fit?
Recheck the collar regularly, particularly for puppies, dogs whose weight changes, or dogs with thick or seasonally changing coats. Also inspect the buckle, stitching and attachment points for wear.
Collar size ranges in our current range
Our collar product pages show the neck range for each available size. For example, several Ralph & Co styles currently run through numbered sizes from 30 or 35 up to 60, but the exact range varies by product. Always use the measurements on the specific product page rather than assuming one brand size fits the same across every design.
Browse our dog collars, or see our dog gear buying guides for more help choosing walking equipment.
Sources and further guidance
General collar-fit guidance is consistent with advice published by Blue Cross and the Kennel Club. Always follow the fitting and care instructions supplied with the exact collar you buy.