Breed Standard - FCI

Jack Russell Terrier

Head: The skull should be flat and of moderate width gradually decreasing in width to the eyes and tapering to a wide muzzle. Stop: Well defined but not over pronounced.
Nose: Black
Muzzle: The length from the stop to the nose should be slightly shorter than from the stop to the occiput.
Lips: Tight-fitting and pigmented black.
Jaws/Teeth: Very strong, deep, wide and powerful. Strong teeth closing to a scissor bite.
Cheeks: The cheek muscles should be well developed.
Eyes: Small dark and with keen expression. Must not be prominent and eyelids should fit closely. The eyelid rims should be pigmented black. Almond shaped.
Ears: Button or dropped of good texture and great mobility.
Neck: Strong and clean allowing head to be carried with poise.
Back: Level. The length from the withers to the root of tail slightly greater than the height from the withers to the ground.
Loin: The loins should be short, strong and deeply muscled.
Chest: Chest deep rather than wide, with good clearance from the ground, enabling the brisket to be located at the height mid-way between the ground and the withers. Ribs should be well sprung from the spine, flattening on the sides so that the girth behind the elbows can be spanned by two hands - about 40 cm to 43 cm. Point of sternum clearly in front of the point of shoulder.
Tail: May droop at rest. When moving should be erect and if docked the tip should be on the same level as ears.
Shoulder: Well sloped back and not heavily loaded with muscle.
Upper arm: Of sufficient length and angulation to ensure elbows are set under the body.
Forelegs: Straight in bone from the elbows to the toes whether viewed from the front or the side.
Forefeet: Round, hard, padded, not large, toes moderately arched, turned neither in nor out.
General appearance: Strong and muscular, balanced in proportion to the shoulder.
Stifle (Knee): Well angulated.
Hock Joint: Low set.
Metatarsus (Rear pastern): Parallel when viewed from behind while in free standing position.
Hind feet: Round, hard, padded, not large, toes moderately arched, turned neither in nor out.
Gait/Movement: True, free and springy.
Hair: May be smooth, broken or rough. Must be weatherproof. Coats should not be altered (stripped out) to appear smooth or broken.
Color: White must predominate with black and/or tan markings. The tan markings can be from the lightest tan to the richest tan (chestnut).
Size and Height: Ideal Height at the withers: 25 cms to 30 cms.
Weight: Being the equivalent of 1 kg to each 5 cms in height, i.e. a 25 cms high dog should weigh approximately 5 kgs and a 30 cms high dog should weigh 6 kgs.

Breed Standard - AKC

Parson Russell Terrier

Head: Strong and in good proportion to the rest of the body, so the appearance of balance is maintained.
Expression: Keen, direct, full of life and intelligence.
Eyes: Almond shaped, dark in color, moderate in size, not protruding. Dark rims are desirable, however where the coat surrounding the eye is white, the eye rim may be pink.
Ears: Small "V"- shaped drop ears of moderate thickness carried forward close to the head with the tip so as to cover the orifice and pointing toward the eye. Fold is level with the top of the skull or slightly above. When alert, ear tips do not extend below the corner of the eye.
Skull: Flat with muzzle and back skull in parallel planes. Fairly broad between the ears, narrowing slightly to the eyes. The stop is well defined but not prominent.
Muzzle: Length from nose to stop is slightly shorter than the distance from stop to occiput. Strong and rectangular, measuring in width approximately 2/3 that of the backskull between the ears.
Jaws: Upper and lower are of fair and punishing strength.
Nose:Must be black and fully pigmented.
Bite: Teeth are large with complete dentition in a perfect scissors bite, i.e., upper teeth closely overlapping the lower teeth and teeth set square to the jaws.
Neck: Clean and muscular, moderately arched, of fair length, gradually widening so as to blend well into the shoulders. Topline: Strong, straight, and level in motion, the loin of moderate length.
Body: In overall length to height proportion, the dog appears approximately square and balanced. The back is neither short nor long. The back gives no appearance of slackness but is laterally flexible, so that he may turn around in an earth. Tuck-up is moderate.
Chest: Narrow and of moderate depth, giving an athletic rather than heavily-chested appearance; must be flexible and compressible. The ribs are fairly well sprung, oval rather than round, not extending past the level of the elbow.
Tail: Docked so the tip is approximately level to the skull. Set on not too high, but so that a level topline, with a very slight arch over the loin, is maintained. Carried gaily when in motion, but when baiting or at rest may be held level but not below the horizontal.
Shoulders: Long and sloping, well laid back, cleanly cut at the withers. Point of shoulder sits in a plane behind the point of the prosternum. The shoulder blade and upper arm are of approximately the same length; forelegs are placed well under the dog. Elbows hang perpendicular to the body, working free of the sides. Legs are strong and straight with good bone. Joints turn neither in nor out. Pasterns firm and nearly straight.
Feet: Round, cat-like, very compact, the pads thick and tough, the toes moderately arched pointing forward, turned neither in nor out.
Hindquarters: Strong and muscular, smoothly molded, with good angulation and bend of stifle. Hocks near the ground, parallel, and driving in action. Feet as in front.
Coat: Smooth and Broken: Whether smooth or broken, a double coat of good sheen, naturally harsh, close and dense, straight with no suggestion of kink. There is a clear outline with only a hint of eyebrows and beard if natural to the coat.
Color: White, white with black or tan markings, or a combination of these, tri-color. Colors are clear. As long as the terrier is predominantly white, moderate body markings are not to be faulted. Grizzle is acceptable and should not be confused with brindle.
Gait: Movement or action is the crucial test of conformation. A tireless ground covering trot displaying good reach in front with the hindquarters providing plenty of drive. Pasterns break lightly on forward motion with no hint of hackney-like action or goose-stepping. The action is straight in front and rear.
Temperament: Bold and friendly. Athletic and clever. At work he is a game hunter, tenacious, courageous, and single minded. At home he is playful, exuberant and overwhelmingly affectionate. He is an independent and energetic terrier and requires his due portion of attention.
Spanning: To measure a terrier's chest, span from behind, raising only the front feet from the ground, and compress gently. Directly behind the elbows is the smaller, firm part of the chest. The central part is usually larger but should feel rather elastic. Span with hands tightly behind theelbows on the forward portion of the chest. The chest must be easily spanned by average size hands. Thumbs should meet at the spine and fingers should meet under the chest. This is a significant factor and a critical part of the judging process. The dog cannot be correctly judged without this procedure.
Size: The ideal height of a mature dog is 14 inches at the highest point of the shoulder blade, and bitches 13 inches. Terriers whose heights measure either slightly larger or smaller than the ideal are not to be penalized in the show ring provided other points of their conformation, especially balance, are consistent with the working aspects of the standard. Larger dogs must remain spannable and smaller dogs must continue to exhibit breed type and sufficient bone to allow them to work successfully. The weight of a terrier in hard working condition is usually between 13 to 17 pounds.
Proportion: Balance is the keystone of the terrier's anatomy. The chief points of consideration are the relative proportions of skull and foreface, head and frame, height at withers and length of body. The height at withers is slightly greater than the distance from the withers to tail, i.e. by possibly 1 to 1½ inches on a 14 inch dog. The measurement will vary according to height.
Substance: The terrier is of medium bone, not so heavy as to appear coarse or so light as to appear racy. The conformation of the whole frame is indicative of strength and endurance.