Krypto–Superman’s dog.
LINK
Yes, I know–he’s alien. But not alien like John Carter’s Martian “dog” Woola.
WOOLA LINK
He looks very–doggy.
So, what kind of dog is Krypto?
I think he’s a Beag-El.
.
Or that’s his Kryptonian name, being a member of the family, as it were…
Or a Spani-El?
Joking aside:
In the comics, Krypto is typically depicted as a Labrador Retriever, though his breed is never explicitly stated and tends to change between artists. At points, he has even been depicted as wolf-like.
His shape definitely looks Lab-ish, but I’ve never seen a Lab in that color.
I always remember him as a all-white Dalmatian. But that goes back to the early 60s - I have no idea how he has been portrayed since.
Time for Niven to write a follow-up: Dog of Steel, Bitch of Kleenex.
His Wiki page suggests Labrador, Dalmation, or White Shepherd.
The comics I read when I was a kid always depicted him with a very short coat, shorter than most Labs or Shepherds, and all-white, unlike most Dalmatians.
The Cretan does look close to the way a lot of artists drew him, although I think Cretans are a bit larger than Krypto was usually depicted.
Super Hound.
Definitely in the working group.
Well muscled.
White. (Decidedly not Dalmatian, they have pokey-dots in their breed standard)
Thin tapered tail
Medium to large size
Special skills are preferred.
Allergies to kryptonite.
Very rare breed. Like, really rare. I mean it. You’ll not find one of your own. Ever.
I dunno… That pic of a Cretan hound has half-cocked ears, compared to Krypto’s floppy ears, and a darker face.
The movie definitely gives me the impression of a Dalmatian… an alien Dalmatian from the planet Krypton. A Kryptatian? A Kryptonian? 
Suppose you were a dog breeder, trying to develop a breed resembling the dog in the comics.
What would you name it?
Kryptonian Hound?
Kryptonian Shepherd?
Überhund?
He’s a very good boy. A good dog. One might even say… super.
That’s what kind of dog he is.
You know, there’s no law that Krypto has to look like a purebred. He could be a Kryptonian version of a Dalmatian/Labrador/Cretan with a coat of a color that evolved to a slightly different color due to Krypton’s red sun.
Or he could be an unacknowledged offspring of Scooby-Doo.
Krypto’s first appearance was in Adventure Comics #210. At that time his face was very different from later versions. He looked more like a 1930s version of a bull terrier.
Compare that to Petey, the Staffordshire terrier from the old Our Gang comedies
Guys, you do remember he’s from another planet, right? Earth breeds may not be relevant. The KKC (Krypton Kennel Club, of course) probably has a whole roster of breeds we know nothing about including one that, as he ages, looks like a bull terrier, a wolf, a very-short-haired lab, etc.
So, enough of this dogger-el.
I once spotted an albino Dalmatian. It was the least I could do.