Pet Carrier Sizes: Airline Limits, Size Chart and How to Measure Your Pet
For anyone buying a carrier for a cat or small dog, flying with a pet in the cabin or choosing a hard kennel for a larger dog. The airline limits, the carrier that suits each pet size and the measurements that decide the fit.
For flying in the cabin, most US airlines accept a soft-sided carrier up to about 18 × 11 × 11 in (46 × 28 × 28 cm), and some are smaller, such as JetBlue at 17 × 12.5 × 8.5 in (43 × 32 × 22 cm). Air France and KLM allow 46 × 28 × 24 cm with a limit of 8 kg (17.6 lb) for pet plus carrier. In practice this fits cats and dogs up to about 15–18 lb (7–8 kg); larger dogs need a hard kennel sized to their body.
- Typical US cabin max
- 18 × 11 × 11 in
- In cm
- 46 × 28 × 28 cm
- EU weight cap (AF, KLM, LH)
- 8 kg incl. carrier
- Soft carrier weight
- 1–2 kg (2–4.5 lb)
On this page
Airline pet carrier size limits (in-cabin, 2026)
A pet in the cabin travels in its carrier under the seat in front of you, so the limit is really the space under an economy seat. That is why most limits cluster around 17–18 in long and 8.5–11 in high. Figures below are the maximum outside dimensions each airline published as of 2026. Airlines change them, and some aircraft have less room, so confirm on the airline's pet page when you book.
| Airline | Max size (in) | Max size (cm) | Notes |
|---|---|---|---|
| American Airlines | 18 × 11 × 11 soft; 19 × 13 × 9 hard | 46 × 28 × 28; 48 × 33 × 23 | Regional (American Eagle) hard limit 16 × 12 × 8 in |
| United Airlines | 18 × 11 × 11 soft; 17.5 × 12 × 7.5 hard | 46 × 28 × 28; 44.5 × 30.5 × 19 | Lower height on some aircraft |
| Delta Air Lines | Varies by aircraft | Varies | Delta asks you to check the seat for your flight; 18 × 11 × 11 in soft carriers are widely used |
| Alaska Airlines | 17 × 11 × 9.5 soft | 43 × 28 × 24 | Two pets of the same species may share one carrier |
| JetBlue | 17 × 12.5 × 8.5 | 43 × 32 × 22 | Soft or hard |
| Southwest Airlines | 18.5 × 13.5 × 8.5 | 47 × 34 × 22 | Some Southwest statements give 9.5 in height; 8.5 in meets both |
| Air France, KLM | 18.1 × 11 × 9.4 | 46 × 28 × 24 | Max 8 kg (17.6 lb) pet plus carrier |
| Lufthansa | 21.7 × 15.7 × 9.1 | 55 × 40 × 23 | Max 8 kg (17.6 lb) pet plus carrier |
Most US airlines set no weight limit in the cabin, but the pet must be able to stand up and turn around inside a carrier that fits the limit. That sets a practical ceiling of about 15–18 lb (7–8 kg) for the animal. A carrier also counts as your personal item or carry-on on most airlines; see the carry-on size rules for the bag allowance that goes with it.
Length is easy to check, but the space under a seat is often only 8–10 in (20–25 cm) high once the seat's frame and the floor rails are counted. A carrier that is 11 in tall only fits if its soft frame compresses. Choose one with a flexible top, and measure it with the pet inside.
Pet carrier size chart by pet weight
Weight tells you which kind of carrier you need. The length and height of the pet decide the exact size.
| Pet weight | Example pets | Carrier | Typical outside size |
|---|---|---|---|
| Up to 8 lb (3.6 kg) | Kittens, Chihuahuas, toy poodles | Small soft carrier | 16–17 × 10–11 × 9–10 in (41–43 × 25–28 × 23–25 cm) |
| 8–15 lb (3.6–6.8 kg) | Most adult cats, Yorkshire terriers, Shih Tzus | Airline soft carrier or small hard carrier | 17–19 × 11–13 × 9–12 in (43–48 × 28–33 × 23–30 cm) |
| 15–20 lb (6.8–9 kg) | Large cats, Maine Coons, small terriers | Largest soft carrier, or 21–24 in hard carrier | 19–24 × 13–16 × 12–15 in (48–61 × 33–41 × 30–38 cm) |
| 15–30 lb (7–14 kg) | Beagles, French bulldogs, cocker spaniels | 28 in plastic kennel | 28 × 20.5 × 21.5 in (71 × 52 × 55 cm) |
| 30–50 lb (14–23 kg) | Border collies, bulldogs | 32 in kennel | 32 × 22.5 × 24 in (81 × 57 × 61 cm) |
| 50–90 lb (23–41 kg) | Labradors, golden retrievers, boxers | 36 or 40 in kennel | 36 × 25 × 27 to 40 × 27 × 30 in (91 × 64 × 69 to 102 × 69 × 76 cm) |
| 90 lb (41 kg) and up | Great Danes, mastiffs | 48 in kennel | 48 × 32 × 35 in (122 × 81 × 89 cm) |
The kennel sizes are Petmate Sky Kennel outside dimensions and the maker's weight bands. Other brands are within an inch or two. For crates used at home rather than for travel, see the dog crate size chart.
Outside size vs inside size
Airlines limit the outside of the carrier; your pet lives in the inside. Plastic walls, the door frame and the base trim take 2–4 in (5–10 cm) off each dimension. Petmate lists the inside of its 28 in kennel as 24.25 × 18.25 × 19.5 in (62 × 46 × 50 cm), about 4 in shorter and 2 in lower than the outside. Soft carriers lose much less, typically under 1 in, which is one reason they dominate cabin travel.
How to measure your pet for a carrier
- Length (A): with the pet standing, measure from the tip of the nose to the base of the tail. Leave the tail out.
- Height (D): measure from the floor to the top of the head, or to the ear tips if the ears stand higher.
- Width (C): measure across the widest point, usually the shoulders.
- Leg height (B): measure from the floor to the elbow joint. You need this only for hard kennels sized by the airline cargo rule below.
- Weigh the pet and add the carrier's weight if the airline has a combined limit, such as the 8 kg (17.6 lb) rule at Air France, KLM and Lufthansa.
For a cabin carrier, the inside length should be at least the pet's length (A) plus 2 in (5 cm), and the pet's standing height (D) should fit without the head pressing on the top. A 10 lb cat that measures 16 in nose to tail base needs an inside length of about 18 in, which is right at the limit of most airlines.
The IATA formula for hard kennels
Kennels for checked or cargo travel must meet IATA Live Animals Regulations Container Requirement 1. The minimum inside size is:
- Length = A + ½B (nose to tail base, plus half the leg height)
- Width = 2 × C (twice the shoulder width)
- Height = D (standing height to the top of the head or ear tips)
Example: a dog with A = 28 in, B = 12 in, C = 9 in and D = 26 in needs an inside of at least 34 × 18 × 26 in (86 × 46 × 66 cm). A 40 in kennel is the smallest that clears that, because a 36 in kennel's inside height is about 2–3 in less than its 27 in outside height. Many airlines now carry pets as cargo only on some routes, so check before you buy a kennel for a flight.
Soft, hard and backpack carriers compared
Soft-sided carriers
- Weigh 1–2 kg (2–4.5 lb)
- Compress to fit under seats, so they suit cabin travel
- Mesh panels on two to four sides for air
Watch out for
- Not accepted for cargo
- Cats can claw through mesh
- Collapse if a heavy bag is placed on top
- Hard plastic carriers are easier to clean, protect the pet in a car and are the only type accepted as cargo. They do not compress, so a hard carrier must be inside the airline limit in every dimension.
- Backpack carriers are usually 12–13 in wide, 10–11 in deep and 16–18 in tall (30–33 × 25–28 × 41–46 cm). The tall shape suits walking, but the height often exceeds cabin limits when the bag is laid flat.
- Expandable carriers have zip-out side panels. They are measured closed for the airline; open them only once you are in the seat area and the crew allows it.
Carriers for car travel and vet visits
In a car, a carrier should sit on the floor behind a front seat or be strapped in with the seat belt through its handle or belt loops. For cats, a hard carrier with a removable top half makes vet examinations easier, because the cat can stay in the base. Choose a size that lets the pet lie down stretched out for trips longer than an hour, which often means one size up from the airline carrier. For the space a litter box or a pet bed takes at the destination, see those guides, and for your own bags the luggage size chart and carry-on bag sizes.
Frequently asked questions
What are the dimensions of an average cat carrier in cm?
A typical soft cat carrier is about 43–48 cm long, 28–30 cm wide and 28–30 cm high (17–19 × 11–12 × 11–12 in). A typical hard plastic cat carrier is about 48 × 32 × 30 cm (19 × 12.5 × 12 in), which is too big for most cabin limits.
Can a soft-sided pet carrier exceed the airline's dimensions?
Only by squashing, and only in height. Airlines allow a soft carrier to compress slightly to fit under the seat, but the pet must still be able to stand and turn around. Gate agents can refuse a carrier that is clearly over the stated length or width.
How much does a pet carrier weigh?
A soft cabin carrier weighs about 1–2 kg (2–4.5 lb). Small hard plastic carriers weigh about 1.5–3 kg (3–6.5 lb). Large plastic kennels for medium and big dogs weigh roughly 5–14 kg (11–30 lb), which counts toward cargo weight and fees.
What size carrier for a 24 pound dog?
A 24 lb (11 kg) dog is too heavy for almost every cabin carrier. It needs a hard kennel of about 28 in (71 cm), the size makers rate for roughly 15–30 lb, or a 32 in kennel if the dog is long-legged. Check that its standing height clears the inside of the kennel.
What size dog fits in a 17 × 11 × 9.5 inch carrier?
Roughly a dog or cat under 15 lb (7 kg) that is no more than about 14–15 in (36–38 cm) from nose to base of tail and can stand with its head under 9 in (23 cm), or lie down and turn around comfortably. Chihuahuas, Yorkshire terriers and small cats usually fit; most dogs over 15 lb do not.
What are hard pet carrier kennel classes?
Plastic kennels are sold by length, usually 21, 24, 28, 32, 36, 40 and 48 in (53 to 122 cm). Some makers number them 100 to 700 instead. The size labels and weight ranges differ by brand, so compare the interior measurements with your pet.