What size cooling mat does your dog or cat need?

The four sizes at a glance

The mistake that costs the most: comparing letters

Size letters in pet products are not standardized. Every maker decides for itself what to call an S or an XL, and the differences are substantial.

Concretely: a 39 × 27 in mat is often sold as an XL. Here that is our L. Someone thinking “the XL was fine last time” who orders an XL from us receives 59 × 39.4 in, which is far more surface than they had in mind. And the reverse is worse: anyone who bought elsewhere and shops by letter here orders one size too small.

Surface area is in any case one of the criteria you can judge any mat by, whatever the brand. The others are on the page about how to choose the best one, along with the question of what a “best tested” label is really worth.

How to measure properly in one minute

First, measure your pet lying down, stretched out on one side, from the tip of the nose to the base of the tail. Not the height at the shoulder, that is no use here.

Second, add 4 to 6 inches. Animals stretch out in their sleep, and the whole point of the mat is for the underside of the body to have as much contact as possible.

Third, compare that number with the long side of the mat. If it only just fits, size up.

There is a second route that works just as well: look at where your pet lies down by themselves in summer, and measure that patch. The stretch of hallway tile, or the spot in front of the patio door, tells you with decent accuracy how much room they take up.

The most registered breeds in the US, and why the weight table matters more

On the American Kennel Club’s 2025 registration figures, the French Bulldog leads for the fourth year running, followed by the Labrador Retriever, the Golden Retriever and the German Shepherd Dog. Which is worth noticing here: the first is a flat-faced breed and the next three are double-coated, so all four need more contact surface than their weight alone suggests.

For a mixed breed the weight table applies directly: up to 11 lb S, up to 33 lb M, up to 55 lb L, 66 lb and over XL. If your dog sits between the L and the XL, take the XL.

The breeds that struggle most, where size matters even more

This is not a footnote: it is the reason surface area counts double with these dogs.

The Golden Retriever and the Labrador Retriever carry a coat that holds heat in. The German Shepherd has a dense undercoat that works as an insulating layer in summer. All three need plenty of contact surface, precisely because the coat slows the heat transfer down anyway: with them, one size up is the safer call.

The French Bulldog is the clearest case, and it is the most registered breed in the country. Dogs regulate temperature almost entirely by panting, and a short-muzzled dog is bad at exactly that. What is left to them is shedding heat through the underside of the body. For that dog, a large enough surface to lie on is not comfort, it is the main route. The same goes for the Pug, the Bulldog, the Boxer and, among cats, the Persian.

Cats: the Maine Coon problem

Among cats the difference in build is wider than people expect, and this table works from standard breed weights.

A Maine Coon does not fit on 19.7 x 15.7 in. It is the largest domestic breed, reaching 18 lb and over three feet with the tail. It needs the M at least. A four-pound Chihuahua, on the other hand, is comfortable on the S, dog or not. That is exactly why we order by weight and not by species. There is more on cats on the page about the cat cooling mat.

Two pets, one household

If your animals get along, one big mat is almost always better than two small ones. They lie down next to each other, and each can shift once their own patch has warmed up. An L at 39.4 x 27.6 in is enough for two medium dogs or three cats.

If they avoid each other, or you want to cover two rooms, separate mats make more sense. That is what the set of three is for: pick two sizes, and the third mat is free, in the smaller of the two, in whichever color you like.