sizing guide for collars

How to Measure Your Dog’s Neck for the Perfect Collar (and Avoid the Most Common Sizing Mistakes)

Finding the right collar or harness for your dog shouldn’t be guesswork, especially if your pup is a professional wiggler or you’re shopping online. A collar that’s too tight is uncomfortable, but one that’s too loose can slip off in the middle of an adventure (cue the heart attack). The good news: you only need a few minutes, a flexible measuring tape, and a treat or two.

Here’s how to make sure you get the perfect fit, every time.

Why Sizing Matters

A properly fitted collar is about safety, comfort, and peace of mind. Too loose? Your dog could back out and run off. Too tight? It can chafe, rub, or even restrict breathing. Getting it right means more freedom and more fun on every walk.

You can always see our visual guide here!!!

Step 1: Gather Your Tools

You’ll need:

  • A soft measuring tape (the kind used for sewing)
  • If you don’t have one, use a piece of string and a ruler
  • Your dog (preferably not napping)
  • Optional: a treat for bribery

Step 2: Measure the Neck

  1. Find the base of your dog’s neck. This is where the collar will sit—not too high behind the ears, and not down on the shoulders.
  2. Wrap the measuring tape around the neck. It should be snug, but not tight. Think “gentle hug,” not “chokehold.”
  3. Check the two-finger rule. Slide two fingers between the tape and your dog’s neck. If it feels comfortable, that’s your number.
  4. Write it down. Round up to the nearest half-inch. If your dog is super fluffy, measure once with the fur fluffed and once with it smoothed down.

Step 3: Consult the Sizing Chart

Using the Aloha Dog Co. fit guide:

Collar Sizing

Size Length (in) Width (in)
Small 10"–15" 0.6"
Medium 13"–21" 0.8"
Large 16"–26" 1"

Pro tip: If your pup is between sizes, always size up for comfort and adjust down.

Harness Sizing

Size Neck (in) Chest (in)
Small 9.5"–11" 11"–17.5"
Medium 11"–14" 15"–22"
Large 15"–23" 23"–37"

For harnesses: Measure both neck and chest (just behind the front legs). Again, go with the larger size if you’re in between.

Step 4: Try It On & Test the Fit

  • Once your collar arrives, fit it to your dog.
  • Check that you can slide two fingers under the collar while your dog is standing.
  • For harnesses, adjust the straps so they’re snug but allow easy movement.
  • Watch your dog walk and play for a few minutes to make sure nothing’s rubbing or pinching.

Common Mistakes to Avoid

  • Guessing based on breed: Every dog is built differently (just like humans).
  • Not accounting for fur: Fluffy coats can add bulk, measure accordingly.
  • Ignoring growth: Puppies and young dogs grow fast! If you’re shopping for a pup, look for adjustable options.

Ready for Your Next Adventure?

Finding the right fit means more worry-free play, beach runs, and sunset hikes. If you need a hand choosing the right size, our customer service is always happy to help.

Check out our full collection of collars and harnesses designed for active dogs who love to explore.

FAQ

Q: What if I’m still not sure on the size?
A: Message us with your measurements and we’ll double-check for you.

Q: Can I exchange if it doesn’t fit?
A: Absolutely. We want your dog to be comfortable, reach out if you need a different size.

Q: Do you have matching leashes?
A: Yes, all of our collections include matching leashes. See the leash section here.

Measure once, order once, and get back to what matters: exploring the world with your dog.

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