What Do Pets Need

Dogs and cats

The crate, bed, harness, carrier and litter box sizes for dogs and cats.

Dog harness and collar sizeType your dog's chest girth and neck, in inches or cm, for its size on the Ruffwear, PetSafe Easy Walk and Hurtta charts. What size crate for my dog?Measure your dog nose to tail base and floor to head, add Petmate's 3 to 4 in or Diggs' 2 to 4 in, and compare inside sizes. What size dog bed?Measure your dog standing, then add Charley Chau's 25 percent or Earthbound's up to 15 cm, and compare with the bed's inside size. What size harness for my dog?Measure the girth behind the front legs and match it to Ruffwear's Front Range, PetSafe's Easy Walk or Hurtta's Seeker chart, in inches and cm. What size collar for my dog?Measure around the neck, match it to Ruffwear's Front Range or Hurtta's Rover chart, and leave room for two fingers under the collar. What size cone for my dog?Wilson Veterinary says to fit a cone to the neck and have it reach several inches past the nose. The Comfy Cone chart, and KONG's E-Collar Cloud by weight. What size dog door?Measure shoulder width and back-to-chest height and pick a flap bigger than both. Ideal Pet and PetSafe flap and cutout sizes, and each door's weight range. What size coat for my dog?Measure back length and chest girth for Hurtta's and Canada Pooch's charts; Ruffwear sizes its coats by girth alone. What size toy or ball for my dog?A toy should be too big to swallow. KONG Classic sizes by weight, KONG's choking line, and Chuckit! Ultra Ball diameters. Airline cargo crate size for dogsIATA's formula: length is nose to tail base plus half the elbow height, width twice the shoulders. With what the crate must be for air travel. What does a new puppy need?The ASPCA's dog supply checklist, with how to size the crate, collar, harness and toys for a puppy that's still growing. What size cat carrier?Measure your cat for the inside size IATA’s formula gives, see which kind of carrier to choose, and why bigger isn’t always better. What size litter box?One and a half times your cat’s length from nose to tail base, rectangular and open, by International Cat Care and the AAFP/ISFM guidelines. How many litter boxes per cat?One per cat plus one extra by four sources, one per cat with a spare by RSPCA, where to put them and how deep to fill them. What does a new kitten need?A litter tray, bed, bowls, carrier and scratching post, then food, toys, a brush and comb and a safety collar, from International Cat Care and ASPCA.

What to measure for dog and cat gear, from crates to litter boxes

What to measure on your pet for each piece of gear, and how its page sizes it
GearMeasureSize
CrateNose to tail base, and floor to head or ear tipsAdd 3 to 4 in (Petmate)
Dog bedNose to tail base, and top of the head to the floorLength and height x 1.25 (Charley Chau)
Airline cargo crateLength, elbow height, shoulder width, standing heightIATA’s formula; 10% larger for snub-nosed breeds
HarnessChest girth, just behind the front legsEach maker’s own chart
CollarAround the neckTwo fingers fit under a flat collar
CoatBack length and chest girthHurtta and Canada Pooch by both, Ruffwear by girth
ConeAround the neck, and neck to snout tipSeveral inches past the nose (Wilson Veterinary)
Dog doorShoulder width; top of the back to bottom of the chestFlap wider and taller than both (Ideal Pet)
Toy or ballThe back of your dog’s mouthToo big to swallow; size up when unsure
Cat carrierNose to tail base, head height, shoulder width, elbow heightIATA’s formula; room to stand up and turn around
Litter boxNose to the base of the tail, and how many cats1.5 times your cat’s length; one per cat, plus one

Each chart is for its maker’s own product, so check the one you buy. RSPCA gives one litter box per cat and calls a spare a good idea.

Where we get our information from

Gear sizes come from the makers’ own charts, and measuring and fit from IATA, International Cat Care, Humane World for Animals and other vet and welfare sources. Checked against published data from Ruffwear, Hurtta, International Cat Care, KONG and Humane World for Animals (plus 11 more).

See all 24 sources
  • IATA, Container Requirement 1, Live Animals Regulations 52nd edition (January 2026), PDF
  • Ruffwear, The Size is Right: How to Measure for Your Dog's Gear (size guide)
  • Ruffwear, Front Range Collar (product page)
  • Ruffwear, Front Range Harness (product page)
  • PetSafe, Easy Walk Harness (product page and sizing chart)
  • Hurtta, Seeker Harness (product page and size chart)
  • Hurtta, Rover Collar (product page and size chart)
  • Hurtta, Walk All-Season Jacket (product page and size chart)
  • Canada Pooch, Size Guide (size chart image)
  • Petmate, All Purpose Kennel - Vari (product page)
  • Ideal Pet Products, Designer Series Ruff-Weather Pet Door, and The easy way to measure your pet (blog)
  • KONG, KONG Classic (product page)
  • KONG, Choosing the Right KONG
  • All Four Paws, Comfy Cone (sizing chart image)
  • Humane World for Animals, Dog collars
  • International Cat Care, Choosing a litter tray for your cat
  • International Cat Care, Preparing for your new cat or kitten
  • International Cat Care, Travelling with your cat
  • AAFP and ISFM Guidelines for diagnosing and solving house-soiling behavior in cats (J Feline Med Surg 2014;16(7):579–598), full text on PubMed Central
  • RSPCA, How to use a cat litter tray
  • ASPCA, General Cat Care
  • Humane World for Animals, How to litter train a kitten or cat
  • Charley Chau, Dog Bed Size Guide
  • Wilson Veterinary (vet clinic), How to Apply an E-Collar to Your Pet at Home

Elsewhere on What Do Pets Need

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General care guidance from animal welfare charities, vets and makers' published sizes. It isn't veterinary advice: if your pet seems unwell or has eaten something it shouldn't, call your vet.