What Size Dog Collar Do I Need?

The No-Faff Guide

Cartoon illustration of Sophia measuring a golden retriever puppy and a spaniel puppy with a tape measure, with a speech bubble reading 'Hold still Milo! Lily you're next.'

You'd think buying a dog collar would be simple. You'd be wrong.

Between the confusing size charts, the "one size fits most" lies, and the collar that arrives and fits your Labrador like a bracelet — it's a minefield. So here's a no-nonsense guide to getting it right first time, with zero guesswork and zero returns.

Step One: Grab a Tape Measure (a Soft One)

The most important thing before you look at any size chart is this: measure your dog's neck properly.

And yes, there is a wrong way to do it.

  1. Find the base of the neck. You want to measure around the base of the neck — that's the lower part, where the collar actually sits day to day. Not the top of the neck near the ears. Not halfway up. The base, where it meets the shoulders.
  2. Keep the tape flat and snug. Keep the tape measure flat against the coat (don't lift it away from the fur), and pull it snug — not tight enough to make your dog give you a betrayed look, but firm enough that it's not flopping around.
  3. Write it down. Write that number down. That's your measurement.

The Ponies & Pups Size Chart

Size Neck Measurement Collar Width
Extra Small 19 – 25 cm 16mm
Small 25 – 31 cm 16mm
Medium 31 – 37 cm 19mm
Large 37 – 43 cm 19mm
Extra Large 43 – 49 cm 25mm

The Golden Rules

  1. Aim for the middle of the range. If your dog measures 28cm, a Small (25–31cm) is perfect — they're sitting right in the middle with plenty of adjustment room either side. If they measure 24cm or 31cm, you're right on the edge.
  2. When in doubt, size up. If your dog sits right on the border between two sizes, always go bigger. A slightly too-large collar can be adjusted. A slightly too-small one is useless.
  3. Check after a big groom. If your dog has a thick, fluffy coat, their measurement in full winter floof will be different to after a summer clip. Worth measuring both ways if your dog has a big seasonal wardrobe change.

What Size Is My Breed?

Every dog is an individual (as they will loudly remind you), but here are some rough starting points based on common breeds. Always measure first — these are guides, not gospel.

Extra Small (19–25cm): Chihuahua, Toy Poodle, Papillon, small Yorkies

Small (25–31cm): Jack Russell Terrier, Miniature Dachshund, Pug, Miniature Schnauzer, Shih Tzu, small Whippets

Medium (31–37cm): Cocker Spaniel, Beagle, Border Terrier, French Bulldog, Cavapoo, Cockapoo, Whippet, Shetland Sheepdog

Large (37–43cm): Springer Spaniel, Border Collie, Dalmatian, Boxer, Standard Poodle, Siberian Husky, smaller Labradors and Golden Retrievers

Extra Large (43–49cm): Labrador, Golden Retriever, German Shepherd, Rottweiler, Weimaraner, larger working breeds

Outliers exist. Milo, my Sprocker Spaniel, has the neck of a dog twice his size because he is built entirely of enthusiasm and bad decisions. Always measure.

What About the Width?

You'll notice that the collar width increases with the size — and that's intentional. A tiny 16mm collar on a Great Dane would look a bit ridiculous, and a 25mm collar on a Chihuahua would practically be a sleeping bag.

The width is automatically matched to the size in our standard collar range, so you don't need to think about it — it just scales correctly.

If your dog is somewhere on the border and you're unsure whether a wider or narrower collar suits them better, feel free to drop us a message — we're always happy to help you figure it out before you order.

Once It Arrives: The Two-Finger Test

When your collar lands and you put it on your dog, you should be able to slide two fingers comfortably underneath without the collar moving around or feeling loose. That's the sweet spot: secure enough not to slip off, comfortable enough that they're not going to be dramatically uncomfortable on a walk.

If it's tighter than that, it needs to go up a size. If it's so loose that it's doing the hokey cokey every time they move, it needs to come down.

Still Not Sure?

Genuinely — just ask. Measuring a wriggly dog is one of life's underrated challenges, and if you're stuck between sizes or have an oddly-shaped neck situation (no judgement, we've seen it all), drop a message via the Contact page before you order.

Every piece of gear from Ponies & Pups is handcrafted to order, so getting the size right matters — and we'd much rather help you figure it out upfront than have you end up with something that doesn't fit.

FIND YOUR FIT

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P.S. If you're measuring a dog who objects to tape measures on principle, a piece of string works just as well. Measure the string against a ruler afterwards. You're welcome.