Dog Collar Size Guide: How to Measure Your Dog's Neck
The short answer: measure around the base of your dog's neck, where the collar actually sits, then add two fingers' width. For most dogs that is somewhere between 2cm and 5cm. If you land between two sizes, go up.
That really is the whole method. The rest of this is how to get an honest number out of a dog who has no intention of standing still, how to turn it into a Pawd size, and the handful of mistakes that make a perfectly good collar fit badly.
What you need
- A soft tape measure, the fabric kind from a sewing kit.
- No tape measure? A bit of string and a ruler does the job perfectly.
- Two fingers. Yours, not someone else's. More on that shortly.
- Thirty seconds, and something your dog would quite like to eat.
How to measure your dog's neck, step by step
Step 1: Find where the collar actually sits
Not up under the jaw, and not down on the shoulders. A collar lives in the middle, roughly two to three finger-widths below the ears, in the natural dip at the base of the neck. That is your spot.
Step 2: Get them on their feet
A sitting dog bunches up the skin at the neck and you will measure a full size too big. Standing, head level, weight on all four paws. If your dog has decided the tape measure is a toy, measure while they are eating. Nobody is watching.
Step 3: Wrap the tape, do not haul on it
Snug against the fur, flat the whole way round, no tension. You are measuring a neck, not strapping down a roof rack. Read the number where the tape meets itself.
Step 4: Add two fingers
Slide two fingers flat between the tape and the neck and read it again. That second number is your collar size. Two fingers is roughly 2cm on a small dog and closer to 4cm or 5cm on a big one, which is exactly why the rule uses fingers instead of centimetres. It scales with the dog, and your hands scale with the dog you tend to own.
Step 5: Do it twice
Measure again a minute later. If the two numbers are more than 1cm apart, you pulled too hard on one of them. Take the larger.
The two-finger rule, and when it lies to you
Two fingers between collar and neck is the standard for an adult dog with a normal coat. Three dogs it does not quite suit:
- Thick double coats (husky, samoyed, chow, groodle in July). Measure through the coat as it is today, then know that the fit will change the moment they are groomed. Lean towards an adjustable collar with plenty of holes.
- Sighthounds (greyhound, whippet, italian greyhound). The head is narrower than the neck, so a normal collar slides straight off over the ears. These dogs want a martingale or a wide limited-slip collar, measured both at the neck and just behind the ears.
- Puppies. Two fingers still applies. You will just be doing it again rather a lot. See below.
Pawd collar size chart
| Size | Neck measurement | Typical dog | Recommended width |
|---|---|---|---|
| XS | 20cm to 25cm | Chihuahua, toy poodle, kitten-sized | 10mm to 15mm |
| S | 25cm to 30cm | Mini dachshund, pomeranian, small cavoodle | 15mm |
| M | 30cm to 38cm | Beagle, cocker spaniel, border collie, corgi | 20mm to 25mm |
| L | 38cm to 48cm | Labrador, golden retriever, boxer | 25mm to 38mm |
| XL | 48cm to 56cm | German shepherd, rottweiler, great dane | 38mm |
Every Pawd collar adjusts within its size, so a measurement sitting near the top of one range and the bottom of the next will work in either. Take the larger. You can always tighten a hole; you cannot add one.
Quick reference by breed
Treat this as a sanity check on your own measurement, never a replacement for it. Dogs vary inside a breed by a genuinely surprising amount.
| Breed | Usual neck | Pawd size |
|---|---|---|
| Cavoodle | 26cm to 33cm | S or M |
| Labrador | 40cm to 48cm | L |
| Golden retriever | 42cm to 50cm | L or XL |
| Border collie | 33cm to 41cm | M or L |
| French bulldog | 33cm to 41cm | M or L |
| Staffy | 38cm to 46cm | L |
| Beagle | 33cm to 40cm | M |
| Dachshund (standard) | 28cm to 36cm | S or M |
| German shepherd | 46cm to 56cm | XL |
| Greyhound | 33cm to 46cm | Martingale, measured separately |
| Pomeranian | 20cm to 28cm | XS or S |
| Cat (adult) | 20cm to 28cm | XS, breakaway only |
Puppies, and the collar you will buy twice
A puppy's neck can put on 1cm a fortnight through the fast months. Check the fit weekly with the two-finger test, and make your peace with buying a second collar.
Most people go through two before the adult size: a small adjustable one from around eight weeks, then the proper one somewhere between six and twelve months depending on breed. Big breeds keep filling out until about eighteen months. Buying the adult size early and running it on the tightest hole does not work, because the spare tail of the collar flaps about and the buckle ends up sitting in the wrong place.
How wide should the collar be?
Width matters more than people expect. Too narrow on a big dog and all the pressure lands on a thin band. Too wide on a small dog and it catches the jaw every time they look down at something interesting.
- Under 5kg: 10mm to 15mm
- 5kg to 15kg: 15mm to 20mm
- 15kg to 30kg: 20mm to 25mm
- Over 30kg: 25mm to 38mm
Sighthounds break the rule again: a wide collar, 38mm or more, spreads the load across a long neck. There is a reason that look has been around for centuries.
Five mistakes that make a good collar fit badly
- Measuring over a thick winter coat and never checking again after a groom. A groodle can lose two full centimetres in an afternoon.
- Measuring while the dog is sitting. Reliably one size too big, every time.
- Pulling the tape tight. You are measuring a neck, not fitting a belt.
- Using the old collar as the measurement. Collars stretch, and the old one may well have been wrong to begin with.
- Sizing down because your dog slips out. If a dog reverses out of a collar, the answer is a martingale or a harness. Never a tighter collar.
Collar, martingale or harness?
| Type | Best for | Avoid when |
|---|---|---|
| Flat collar | Everyday wear, ID tags, dogs who walk calmly | Dog pulls hard or has a narrow head |
| Martingale | Sighthounds, escape artists, gentle correction | Unsupervised wear, because the loop can catch |
| Harness | Pullers, puppies, flat-faced breeds, neck or throat issues | Nothing much, though you still want a collar for ID |
| Breakaway collar | All cats, always | Never clip a lead to one |
Measuring a cat
Same method, smaller numbers, one rule that is not up for discussion: the collar must have a breakaway clasp. Cats climb, cats get caught, and a collar that cannot let go is a hazard. Measure the neck, add one finger rather than two, and check it weekly. Most adult cats land between 20cm and 28cm.
Frequently asked questions
How tight should a dog collar be?
Snug enough to stay put, loose enough to slide two fingers flat underneath. Three fingers and your dog can reverse out of it. If one finger is a squeeze, it is too tight.
Where exactly do I measure my dog's neck?
At the base of the neck, in the natural dip where it meets the shoulders, roughly two to three finger-widths below the ears. It is lower than most people guess, and it is where the collar will actually sit.
Should I measure my dog's neck or just use their weight?
Measure. Weight is a terrible predictor of neck size: a 20kg staffy and a 20kg border collie want completely different collars. Breed charts are a sanity check, not a method.
What if my dog is between two sizes?
Take the larger. Every Pawd collar adjusts down within its range, so the bigger size will come back to your measurement. The smaller one may never reach it.
How do I measure a dog who will not sit still?
Measure while they are eating, or get a second person to hold a treat at nose height so the head stays level. If all else fails, loop a piece of string round, pinch it with your thumb, and measure the string later in peace.
How often should I check the fit?
Weekly for puppies, after every groom for long-coated breeds, and every few months for an adult. Weight, seasonal coat changes and plain old stretch all move the fit without telling you.
Can a collar be too tight without me noticing?
Yes, and the signs are easy to miss: hair loss or a flattened ring in the coat where the collar sits, coughing on the lead, scratching at the neck, or suddenly being hard to catch at collar time. Check with two fingers, not by eye.
My dog keeps slipping out of their collar. What should I do?
Do not tighten it. A dog who backs out of a collar usually has a head narrower than their neck, which is a shape problem rather than a sizing one. A martingale tightens just enough to stop the escape without choking, and a harness removes the question altogether.
What size collar does a puppy need?
Measure now, buy for now. A puppy collar should fit today with room left on the adjustment, not fit in six months' time. Expect to replace it once or twice before you land on the adult size.
Is leather or webbing better?
Leather softens to the shape of the neck, lasts longer and ages well, but it does not enjoy being soaked every weekend. Webbing is lighter, washable and the better call for a dog who swims. Both are good. It depends entirely on what your dog's week looks like.
Do cats need a different kind of collar?
Yes. Cats need a breakaway clasp that releases under sustained pressure, because cats climb and cats get caught. Never put a dog collar on a cat, and never clip a lead to a breakaway collar.
How much room should there be under a cat collar?
One finger, not two. Cats have smaller necks and far more flexible shoulders, and a two-finger gap on a cat is wide enough for a front leg to find its way through.
Still not sure?
Send us the measurement and the breed and we will tell you which size to order. If it turns up and the fit is wrong, send it back within 30 days and we will swap it.
