The first list of show points was published by J.H. Walsh under the pseudonym of "Stonehenge" in 1878 in his book Dogs of the British Islands.
The next standard was issued by the Pug-Dog Club in England in 1883.
The Scottish Pug-Dog Club issued their own breed standard in 1925, with as sole difference a slightly lighter weight (13 to 17 lb. instead of 14 to 18 lb.).
The breed standard drawn up in the 1880s remained virtually unaltered to this day.
Official Pug Breed Standards
(AKC, FCI and Kennel Club Pug Breed standards)
The main difference between the AKC, FCI and Kennel Club Pug breed Standards are the definition of the Pug colors: the AKC recognizes three Pug colors, while the FCI and Kennel Club standard mention four colors. In fact, we think this divergence just confirms a plausible misinterpretation of the original breed standard, which mentioned different shades of fawn (silver(-) and apricot-fawn), not separate colors in addition to fawn.
For more information about the standard Pug colors and the missing-hyphen-theory, see: Pug colors.
The AKC Pug standard also adds a description of the wrinkles (which should be "large and deep"). The description of the forequarters and hindquarters is more detailed: the pasterns (should be "strong, neither steep nor down"), dewclaws ("are generally removed"), thighs and buttocks ("are full and muscular").
The FCI standard adds to the description of the tail that it should be high-set.
Official Standard of the Pug
(Original Pug Champion Characteristics)
Symmetry and general appearance, decidedly square and cobby. A lean, leggy Pug and a dog with short legs and a long body are equally objectionable.
Size and Condition
The Pug should be multum in parvo, but this condensation (if the word may be used) should be shown by compactness of form, well-knit proportions, and hardness of developed muscle. Weight from 14 to 18 pounds (dog or bitch) desirable.
Short and cobby, wide in chest and well ribbed up.
Very strong, straight, of moderate length, and well under.
Neither so long as the foot of the hare, nor so round as that of the cat; well-split-up toas, and the nails black.
Short, blunt, square, but not upfaced.
Large, massive, round - not appleheaded, with no indentation of the skull.
Dark in color, very large, bold and prominent, globular in shape, soft and solicitous in expression, very lustrous, and, when excited, full of fire.
Thin, small, soft, like black velvet. There are two kinds - "Rose" and "Button". Preference is given to the latter.
Clearly defined. The muzzle or mask, ears, moles on cheeks, thumb marks or diamond on forehead, back-trace should be as black as possible.
The mask should be black. The more intense and well defined it is the better.
Large and deep.
A black line extending from the occiput to the tail.
Fine, smooth, soft, short, and glossy, neither har nor woolly.
Silver or apricot-fawn. Each should be decided, to make the contrast complete between the color and the trace and the mask. Black.