Dog Coat Size Guide: How to Measure Chest Girth, Neck & Back Length

Dog sitting indoors with a measuring tape, looking curious while deciding what size coat to choose

 

Not sure what size dog coat to buy? You’re not alone—fit is everything. 🐶💛 In this quick guide, you’ll measure chest girth, neck girth, and back length (the 3 numbers that matter most). Follow the steps below, compare your measurements to the size chart on each coat, and enjoy cozy walks with fewer returns and happier tails.

 

 

Dog Coat Size Guide: How to Measure Your Dog

A great dog coat should feel snug, cozy, and easy to move in—never tight, never floppy. To find the best fit, you’ll take three measurements while your dog is standing naturally on all fours: chest girth, neck girth, and back length. A soft tape measure works best, but string + a ruler works too.

 

Soft tape measure and dog treats laid out on a wooden surface for measuring a dog at home

What you’ll need

  • Soft tape measure (recommended) or string + ruler
  • Treats (seriously—this helps 😄)

 

Person measuring a dog’s chest girth by wrapping a measuring tape around the widest part of the dog’s chest

Step 1: Measure Chest Girth (MOST important for dog coats)

  1. Have your dog stand up straight.
  2. Measure around the widest part of the rib cage, usually just behind the front legs.
  3. Keep the tape snug but not tight—use the two-finger rule (you can slip two fingers between tape and dog).
  4. If your dog has thick fur, press the tape closer to the body so fluff doesn’t add extra inches.

✅ Write this number down first — most coat sizing is built around chest girth.

 

Person measuring a dog’s neck girth with a soft measuring tape placed where the collar sits

Step 2: Measure Neck Girth

  1. Measure around the base of the neck where the collar normally sits.
  2. Again, keep it comfortable using the two-finger rule.
Person measuring a dog’s back length from the base of the neck to the start of the tail using a measuring tape

Step 3: Measure Back Length

  1. Measure from where the neck meets the shoulders (near the withers) to the base of the tail.
  2. Do this while your dog is standing (not sitting) for the most accurate result.

 

Golden retriever wearing a waterproof dog jacket while standing outdoors on a walking path

How to choose the right coat size (using all 3 measurements)

Use this simple order:

  1. Start with chest girth → pick the size where your dog’s chest measurement fits comfortably in the chart range.
  2. Check neck girth → if your dog’s neck is near the top of the range, consider sizing up (especially for fluffy breeds).
  3. Check back length → choose the size that gives coverage without going past the tail base.

If your dog is between sizes

We recommend choosing the larger size for comfort and movement (then adjust using straps/closures if available).

 

Properly fitted dog coat showing secure chest and neck, full back coverage, and unrestricted leg movement

How a dog coat should fit (quick checklist)

A good fit means:

  • Chest and neck feel secure, not tight (two-finger rule)
  • Front legs move freely (no rubbing in the “armpit” area)
  • Coat covers the back nicely without restricting potty breaks
  • No gaping at the chest and no twisting to one side

Frequently Asked Questions

1) What measurement matters most for dog coats?

Chest girth is usually the #1 sizing measurement for coats.

2) My dog is fluffy—should I measure over fur?

Measure snugly and press closer to the body so fur doesn’t inflate the number.

3) If my dog is between sizes, do I size up?

In most cases, yes—comfort and mobility win.

4) Can I use string instead of a tape measure?

Yes—wrap string, mark it, then measure it with a ruler.

5) Why does back length matter?

It ensures the coat covers the back properly without being too short or too long.

Ready for the Right Size? Browse Dog Coats & Jackets

Now that you’ve got your dog’s measurements, choosing the right coat is easy. Shop our warm, waterproof dog coats and jackets designed for a comfy fit and happy walks — even on cold, rainy days.