How to Measure Your Dog
Proper fit is the difference between gear that performs and gear that fails. Two measurements. Five minutes.
Quick Reference
If you already have your dog's back length measurement, find the right size here.
Back length is the primary fit determinant. Our chest and neck closures adjust across a wide range, so a span of girths fits each size. If you are between sizes, size up.
Breed Starting Points
Use these as a starting point only. Individual dogs within a breed can vary significantly. Always measure.
XXS
Toy Poodle, Pomeranian, Yorkshire Terrier, Maltese, Chihuahua
XS
Dachshund, Scottish Terrier, Miniature Poodle, Papillon, Italian Greyhound
S
Beagle, Corgi, French Bulldog, Miniature Schnauzer, Shiba Inu, Cocker Spaniel, Jack Russell Terrier
M
Border Collie, Australian Shepherd, English Springer Spaniel, Standard Schnauzer, Vizsla
L
Labrador Retriever, Golden Retriever, Akita, Weimaraner, Doberman, Malamute
How to Measure
You need a soft measuring tape or a length of cord you can measure against a ruler. Back length sets the size. Chest girth confirms it.
Back Length
The most important measurement
Measure from the base of the neck (where the collar sits) to the base of the tail. Keep your dog standing naturally, not stretched out or hunched.
Tip: Our chest and neck closures adjust across a wide range, so back length is what sets the size. The cut covers most of this length and wraps under the belly.
Chest Girth
Confirms the size
Measure around the widest part of your dog's ribcage, just behind the front legs. Keep the tape snug but not tight. You should be able to slip two fingers underneath.
Tip: If your dog has a deep chest (like a Greyhound or Doberman), measure at the deepest point. If the girth lands above the range for the size back length gives you, size up.
Size Chart
All measurements in inches. Back length determines size selection. Chest girth confirms it.
| Size | Back Length | Chest Girth | Approx. Weight Range |
|---|---|---|---|
| XXS | 6-12" | 9–17" | 4–12 lbs |
| XS | 11-17" | 14–22" | 8–20 lbs |
| S | 16–21" | 17–26" | 15–30 lbs |
| M | 20-26" | 21–32" | 25–60 lbs |
| L | 25–32" | 26–38" | 50–100 lbs |
Weight is a rough reference only. A muscular 45 lb dog and a lean 45 lb dog can differ by two sizes. Always measure.
Fit Notes
Between Sizes?
Go up. Our gear is designed to layer, and a slightly roomier fit won't affect performance. Too tight restricts movement and can cause chafing on long days.
Deep-Chested Breeds
Greyhounds, Dobermans, Whippets, and similar breeds carry more girth than their back length suggests. Start from back length, then check chest girth. If the girth lands above the range for that size, size up.
Barrel-Chested Breeds
Bulldogs, Pugs, and similar breeds pair a short back with a large girth. Size for back length. The adjustable chest and neck closures take up the difference. If the girth still exceeds the range, size up.
Long, Low Builds
Dachshunds, Corgis, and similar breeds carry a long back on a small girth. Size for back length so the layer covers the core. The closures cinch down to fit the girth.
Puppies
Measure your puppy as they are now. If they're still growing, consider waiting until they've reached adult size, or accept that you may need to size up in a few months.
Layering
If you're buying a shell to go over our fleece or puffy, all three products are designed to work together in the same size. No need to size up for layering.
Proper Fit Check
When fitted correctly, you should be able to slide two fingers under any strap or closure. Your dog should move freely-watch for any restriction in their gait.
Need a Second Opinion
Send us your dog's back length and chest girth measurements along with a photo, and we will recommend the right size.
Get a Fit RecommendationOr email us: support@sundialdoggear.com