Short answer: wrap a soft tape around the base of your dog's neck, where the collar sits, and add 1 to 2 inches. Check the fit by sliding two flat fingers under the collar. The size chart below turns that number into XS through XL.
Why Getting the Right Collar Size Matters
A well-fitted collar is one of the most important things you can do for your dog's comfort and safety. A collar that's too tight can cause skin irritation, restrict breathing, and become painful as your dog moves. Too loose, and your pup can back right out of it, which is a real safety risk, especially near traffic or in unfamiliar places.
The good news: measuring your dog's neck takes about 30 seconds and a soft measuring tape. Here's how to do it properly.
What You'll Need
- A soft fabric or flexible measuring tape (a tailor's tape is ideal)
- A pen and paper to note the measurement
- A treat to keep your dog still (always optional, rarely unwelcome)
If you don't have a fabric tape measure, a piece of string and a ruler work just as well.
Step-by-Step: How to Measure Your Dog's Neck for a Collar
Step 1: Find the Right Spot
Measure at the base of your dog's neck, the area where the collar naturally sits, a few inches above the shoulders. This is lower than where you might measure for a human necklace. For most dogs this is the widest part of the neck, which gives you the most accurate and comfortable fit. It's the same spot the American Kennel Club's measuring guide uses.
Step 2: Measure the Circumference
Wrap the measuring tape around your dog's neck at that spot. Hold it snug but not tight. You should be able to slip two fingers underneath the tape comfortably. That two-finger rule is the standard gauge for a proper collar fit.
Note the number where the tape meets itself. That's your dog's neck circumference.
Step 3: Add 1 to 2 Inches
Add 1 to 2 inches to the measurement you just took. This is your collar size. The extra room accounts for the two-finger gap and ensures the collar sits comfortably without pressing against the skin.
For example: if your dog's neck measures 12 inches around, look for a collar sized 13 to 14 inches.
Step 4: Double-Check the Fit
Once the collar is on, do the two-finger test again with the actual collar. Slide two fingers (index and middle finger, flat against the neck) underneath the collar. It should feel snug but not tight. If you can't fit two fingers, loosen it a notch. If three fingers slide in easily, tighten it one notch. The AKC gives the same test: if two fingers won't fit, the collar is too tight.
Dog Collar Size Chart
While every dog is different, here's a general size guide to give you a starting point:
| Size | Neck measurement | Example breeds |
|---|---|---|
| Extra Small (XS) | 6 to 11 inches | Chihuahuas, toy breeds, puppies |
| Small (S) | 10 to 14 inches | Dachshunds, Beagles, Shih Tzus |
| Medium (M) | 13 to 18 inches | Cocker Spaniels, Bulldogs, Border Collies |
| Large (L) | 17 to 22 inches | Labradors, Golden Retrievers, Boxers |
| Extra Large (XL) | 20 to 26 inches | Great Danes, Mastiffs, Saint Bernards |
Sizes overlap on purpose: if your dog's measurement falls in two sizes, check the exact range on the product's own size chart, since makers size a little differently. Still a tie? Go with the larger size, which is also the AKC's advice. Always measure first and use size charts as a secondary reference. Breed generalizations can vary widely even within the same breed.
Special Considerations
Puppies
Puppies grow fast. If you're buying a collar for a puppy, choose one with multiple adjustment holes and plan to re-measure every few weeks. Many puppies can grow through two or three collar sizes in their first year alone.
Thick-Coated Breeds
If your dog has a thick or fluffy coat like a Husky, Samoyed, or Golden Retriever, measure through the fur, not to the skin. The collar will sit on top of the coat, so that's what you're fitting.
Greyhounds and Sighthounds
Breeds like Greyhounds, Whippets, and Italian Greyhounds have necks that are wider than their heads, which means standard collars can slip off easily. These breeds do best with a martingale collar, which tightens slightly when pulled and prevents escape without choking. Greyhound adoption groups such as Greyhounds As Pets NSW recommend martingales for exactly this reason.
Cats
Cat collars should always have a safety breakaway buckle. Measure around the base of the neck and fit the collar so two fingers slide underneath. That's the fit used in an Ohio State University study of 538 cats, published in the Journal of the American Veterinary Medical Association: nearly three in four cats wore their collars for the full six months, and collars caught on the mouth, a leg or an object for about 3% of the cats. A breakaway buckle is the safety net for those rare snags. Shop our breakaway cat collars.
When to Re-Measure
It's worth re-checking your dog's collar fit at least once a season, and any time you notice your dog scratching at their neck, coughing while on leash, or if the collar starts to look visually tight. Weight changes from a diet, aging, or a health condition can also shift the fit significantly.
FAQ
Where do I measure my dog's neck for a collar?
Measure at the base of the neck, where the collar naturally sits, a few inches above the shoulders. For most dogs that is the widest part of the neck, which gives the most accurate and comfortable fit.
How much should I add to my dog's neck measurement?
Add 1 to 2 inches to the measured circumference. If your dog's neck measures 12 inches, look for a collar sized 13 to 14 inches. The extra room covers the two-finger gap so the collar sits comfortably without pressing on the skin.
How tight should a dog collar be?
Snug but not tight. With the collar on, slide two flat fingers underneath: if they do not fit, loosen a notch; if three fingers slide in easily, tighten one notch.
How often should I re-measure a puppy for a collar?
Every few weeks. Choose a collar with several adjustment holes, because many puppies grow through two or three collar sizes in their first year.
Shop Collars at Gussied Up
Now that you've got the perfect measurement, browse our full collection of handcrafted and designer dog collars, from everyday plaids and florals to seasonal styles and premium Foggy Dog designs. Each product listing includes a detailed size chart so you can shop with confidence.
Shop All Dog Collars at Gussied Up →
Sources
- How to Measure Your Dog for Clothes and Gear, American Kennel Club
- Choosing the Right Collar for Your Dog, American Kennel Club
- Why you should be using a Martingale collar, Greyhounds As Pets NSW
- Study: 3 out of 4 cats will wear a collar, The Ohio State University, on Lord et al., Journal of the American Veterinary Medical Association, 2010
Shop this guide
- All dog collars — every listing carries a size chart
- Water-resistant collars — for dogs who find every creek
- Foggy Dog — designer prints with solid brass hardware
