How to Measure Your Dog for a Collar or Harness

How to Measure Your Dog (Properly)

The single biggest reason a collar doesn't fit isn't the size chart — it's the measurement. Most people guess. Don't guess. A 60-second measurement gets you a collar that fits perfectly on day one and stays comfortable for years. Here's exactly how to do it.

What You'll Need

  • A soft tape measure (the cloth kind tailors use)
  • If you don't have one — a piece of string and a regular ruler will work
  • Your dog, standing up, calm

How to Measure for a Collar

Step 1. Stand your dog up. Sitting changes the neck shape — measure them on all four feet.

Step 2. Wrap the tape around the base of their neck, where their collar would naturally sit (just above the shoulders, below the jaw). Don't pull it tight. The tape should rest comfortably on the fur.

Step 3. Read the measurement. This is your neck size.

Step 4. The two-finger rule. Add enough room to fit two fingers flat between the tape and your dog's neck. For most dogs that's about 1–2 inches added to the bare measurement. This is the size collar you want.

Quick reference:

  • Small dogs (Yorkies, Chihuahuas, small terriers): 8–12"
  • Medium dogs (Beagles, Cocker Spaniels, mid-size mixes): 12–16"
  • Large dogs (Labs, Golden Retrievers, GSDs): 16–22"
  • Extra-large dogs (Mastiffs, Great Danes, Saint Bernards): 22–28"

If your dog falls between sizes, go up — collars are adjustable down, not up.

How to Measure for a Harness

Harnesses need two measurements: neck (same as above) and chest/girth.

For chest/girth: Wrap the tape around the widest part of the rib cage, just behind the front legs. Use the two-finger rule again — the harness should be snug but never tight enough to restrict breathing or shoulder movement.

How to Measure Leash Length

Most everyday situations call for a 4–6 foot leash. Here's how to choose:

  • 4 feet: Best for city walks, training, and high-traffic areas where you want close control.
  • 5 feet: The all-purpose leash. Comfortable for most walks, parks, and trails.
  • 6 feet: Best for trails, open spaces, and dogs who like a little more room to roam.

Common Mistakes (and How to Avoid Them)

Mistake 1: Measuring a sitting dog. The neck shape changes when a dog sits. Always measure standing.

Mistake 2: Pulling the tape tight. A tight tape gives you a too-small reading. Let it rest naturally on the fur.

Mistake 3: Measuring over a thick winter coat. If your dog has a heavy double coat, measure right at the skin or factor in fur compression.

Mistake 4: Forgetting that puppies grow. If your dog is under a year old, expect to size up at least once. Our adjustable collars give you 2–3 inches of growth room.

How a Properly Fitted Collar Should Look

You should be able to slide two fingers comfortably between the collar and your dog's neck. Not loose enough to slip over the head — not tight enough to compress the fur. The collar should sit just above the shoulders, not riding down on the chest or up under the jaw.

Still Not Sure? We're Here.

If you're between sizes, have an unusual breed, or just want a second opinion — email us at info@eurodogcollars.com or give us a call. We've been making collars for nearly 30 years and we'd rather spend two minutes on the phone with you than ship something that doesn't fit.

Our Promise: If your collar doesn't fit, send it back. We'll exchange it. Every Euro-Dog product is backed by our 1-Year Guarantee with no fine print.