How to Measure Your Dog for a Collar

A collar size like “medium” or “large” isn’t enough on its own. Start with your dog’s neck measurement, then compare it with the size chart for the exact collar you’re buying.

Measure before you order

1. Use a flexible measuring tape around the part of your dog’s neck where a regular flat collar will sit. Keep it snug without pulling it tight or compressing the fur.
2. If you don’t have a measuring tape, use a piece of string, mark the length, and measure it against a ruler.
3. Check the product’s sizing instructions. Some charts use your dog’s neck measurement; others list the collar’s adjustable range. Don’t add extra inches unless the instructions tell you to.
4. When the collar arrives, adjust it and check the fit. For a regular flat collar, you should generally be able to slide two fingers underneath comfortably. It shouldn’t press into the neck or be loose enough to slip over the head.
5. Recheck the fit as your dog grows, changes weight, or gets a haircut.

Between sizes?

Compare the adjustment ranges instead of guessing from breed or weight. If the chart is unclear, ask about that specific collar before ordering.

Buying a training collar?

Prong collars and other specialized training collars have different fitting requirements. Don’t use the regular flat-collar fit check as a substitute for the manufacturer’s instructions or guidance from a qualified trainer.

Ready to compare options?

Browse ReStock K9’s Collars & Leashes collection, then check the sizing details on the product you choose.