Dog Collar Size Calculator
Find the safest neck fit and collar width for everyday use, training, or a snug, escape-safe fit.
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Recommended collar size
This is a starting estimate. Check the brand size chart and make sure you can fit two fingers under the collar.
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Adjusted target
- Neck target: 43.1 cm
- Width guide: 1-1.5 in / 2.5-3.8 cm
- Weight guide: 7.1-11 in / 18-28 cm
This is a starting estimate. Check the brand size chart and make sure you can fit two fingers under the collar.
Frequently Asked Questions
How tight should a dog collar be?
A safe collar usually lets you slip two fingers between the collar and your dog's neck. Too tight can irritate the skin and too loose can slip off.
Is neck girth or weight more important?
Neck girth is the primary measurement because it determines the actual fit. Weight is still useful as a backup check, especially for dogs with broad or muscular necks.
Should I size up if my dog's neck is between two sizes?
Usually yes, as long as the larger collar still leaves enough room to adjust snugly. The goal is comfort and safety, not a collar that floats around the neck.
Do wider collars make a difference?
Yes. Wider collars spread pressure over a larger area, which can be more comfortable for stronger or larger dogs. Smaller dogs usually do better with narrower collars.
This site provides estimates and planning tools only. It does not replace veterinary advice, diagnosis, or treatment.