To measure a dog for a coat, you need three numbers: chest girth, back length and neck. It takes about two minutes with a soft tape measure and a few treats. Chest usually decides the size, and the other two tell you whether that size will fit your dog's shape.
Here's how to take each measurement, how to read a size chart, and how to check the fit at home before the first cold walk.
What you need
- A soft tape measure. No tape? Use a piece of string or ribbon, mark where it meets, then lay it flat along a ruler.
- A few small treats to keep your dog standing still.
- A helper, if your dog is the wiggly type.
- Something to write on. Measure in inches, since most US size charts use them.
How to measure your dog, step by step
- Get your dog standing. All four feet on the floor, head level. Sitting or lying down changes the shape of the chest and back, so the numbers come out wrong.
- Chest girth. Wrap the tape around the widest part of the rib cage, just behind the front legs. Keep it snug but not tight: you should be able to slip two fingers under the tape.
- Back length. Measure along the spine from the base of the neck, where a collar sits, to the base of the tail.
- Neck. Measure around the neck where the collar sits, again with two fingers of room.
- Measure twice. Take each measurement again, and use the bigger number if they differ.
Weigh your dog too if it's easy, but treat weight as a rough guide. Two dogs with the same weight can have very different chests.
The American Kennel Club's measuring guide uses the same three measurements and notes that chest girth is usually the most important one for clothing.
Which measurement matters most?
It depends on how the coat goes on.
- Pullover coats and sweaters go over the head and front legs, so chest comes first and neck second. If the neck opening is too small, every walk starts with a wrestling match. Our Fleece Turtleneck Dog Coat is a pullover with snaps at the back of the neck, which makes it easier to get on.
- Wrap coats with straps fasten around the body, so the chest has some give. Back length matters more, because a strap can't make a coat longer.
- Vests that fasten along the back go by chest first, then back length. Our Sherpa Dog Vest buttons down the back and is sized by chest.
How to read a size chart
Every brand sizes differently, so always use the chart for the exact coat you're buying. A medium in one brand can be a large in another.
- Find the size where your dog's chest falls inside the range.
- If your dog fits two sizes, compare back length and neck to decide.
- If they're still between sizes, go up one. A slightly roomy coat is more comfortable than one that pinches.
Here's an example using our fleece coat's chart. A dog with an 18-inch chest fits both M (15.0–18.1 in) and L (16.9–20.9 in). If their back is about 14 inches, the L, with a 14.2-inch back length, is the better match. If they're compact, with a back closer to 12 inches, the M (12.6 in) will sit better.
Breed names and weights on a size chart are only a starting point. Your tape measure knows your dog better than a breed label does.
Body shapes that need a second look
- Deep chest, narrow waist (greyhounds, whippets and other sighthounds): a coat that fits the chest can hang loose around the waist. Look for a band or strap under the belly that pulls it in.
- Stocky and broad (French bulldogs, pugs, English bulldogs): the size that fits the chest is often too long in the back. A shorter cut helps. Our sherpa vest has a short cut that suits stocky small-to-medium dogs best.
- Long and low (dachshunds, corgis, basset hounds): back length and belly clearance matter as much as chest. Check that the coat doesn't drag or bunch up between the front legs.
- Fluffy coats: press the fur down lightly as you measure, the way a coat will. Many thick, double-coated breeds don't need a coat at all.
- Puppies: buy for the size they are now, not the size they'll grow into. A loose coat can slip, twist or tangle their legs. Re-measure every few weeks.
Check the fit at home
Try the coat on indoors first, on a calm day, with treats nearby. Then check:
- Neck and chest: you can slip two fingers under the fabric.
- Front legs: your dog can walk, sit and lie down without the coat rubbing their armpits or pulling across the shoulders.
- Belly: for male dogs, the belly band sits far enough forward that they can pee without soaking it.
- Length: the coat ends around the base of the tail and doesn't cover it.
- Leash access: if you walk on a harness, you can still reach the leash ring. Our fleece coat has an opening on the back for this.
Watch your dog for a few minutes. Scratching at the coat, freezing in place or trying to back out of it can mean the fit is off, or that they need more time to get used to it.
If a coat or vest from us doesn't fit, you can exchange it for another size within 30 days of delivery, as long as it's clean, unwashed, free of pet hair and still tagged. That's why the indoor fit check is worth doing. The details are in our refund policy.
Helping your dog get used to wearing it
Some dogs accept a coat without a second thought. Others freeze like a statue the first time. Go slowly:
- Let your dog sniff the coat, then give a treat.
- Drape it over their back for a few seconds, treat, and take it off.
- Fasten it for short stretches indoors, with treats or a game.
- Head out for a short walk once they're relaxed wearing it at home.
It's the same slow, treat-based approach we suggest for introducing a calming wrap in our fireworks guide.
Does your dog need a coat?
Not every dog does. The American Kennel Club lists the dogs most likely to benefit: small and toy breeds, hairless breeds, dogs with clipped coats, dogs built low to the ground, lean dogs, short-coated sporting breeds, young puppies, seniors, and dogs with conditions like arthritis. Big dogs with thick double coats, like huskies, malamutes and Bernese mountain dogs, are built for the cold.
Whatever your dog wears, take the coat off indoors, and take it off if your dog seems too warm or pants hard. A fleece coat is for cool, dry days. It isn't waterproof, so dry your dog off after wet walks.
FAQ
Should a dog coat be tight or loose?
Snug, not tight. You should be able to slip two fingers under it at the neck and around the chest, and your dog should move freely.
My dog is between sizes. Which should I pick?
Usually the larger one. Check back length first, though: if the bigger size is much longer than your dog's back, it can bunch up or get in the way when they pee.
Can I pick a size by weight?
Only as a rough guide. Chest girth is more reliable, because dogs of the same weight can be built very differently.
How often should I re-measure?
Every few weeks for a growing puppy. For adult dogs, re-measure each fall, and after a big change in weight or a short haircut.
The short version
- Measure chest, back length and neck with your dog standing, using a soft tape or a piece of string.
- Leave two fingers of room under the tape.
- For pullover coats, chest decides the size. For wrap coats with straps, back length matters more.
- Use the chart for the exact coat you're buying, and go up a size if your dog is between two.
- Check the fit indoors: two fingers of room, free front legs, and a belly band that stays clear for male dogs.
- Introduce the coat slowly with treats, and take it off indoors.
Choosing between a warm coat and a snug wrap for noisy nights? How to choose a calming product for your dog explains what a wrap can and can't do.