Historically, this breed has been known since the remote past of the Czech state. Because of its small size, quick movement and highly developed sense of smell it was used for killing rats (which gave it the name "Krysařík" = Ratter). This quality was gained during its long historical development. This small active dog was often seen at aristocratic feasts of Czech kings at the Prague castle. It adorned courts of Bohemian aristocracy and as a gift from Bohemian kings it came to other European rulers and later to the ordinary citizens. The search of historical facts resulted in proofs that this breed really is of Bohemian origin and can be traced to the early history of the Czech nation. In 1980 its regeneration successfully started. Pražský krysařík is again a favourite pet that lives as a family dog and is becoming popular also in many other countries worldwide.

A small smooth-haired or medium long coated dog with an almost square and compact body. Despite its small size it is a very active, alert and lively dog. Sexual dimorphism should be clearly defined.

IMPORTANT PROPORTIONS:
Relation of height at withers to length of body (measured from point of shoulder to point of buttocks) should be 1:1.05. Females may be slightly longer.

Depth of chest should be in ideal case half of height at withers.
Skull width should be identical to skull length. The skull must not be wider than longer.
Muzzle should be one third up to less than one half of the total length of the head with distinct stop.
These proportions should be considered as ideal ones, but the general appearance is more important.

Gentle, curious and affectionate. Quick with good movement and steady pace. By nature slightly reserved towards strangers but very friendly in the family. With natural nobility and character.

CRANIAL REGION:
Skull: In profile rounded, not parallel with muzzle, occiput is visible. Eyes are set wide apart. Skin on skull has no folds and is coated with short and fine hair.
Stop: Distinct.

FACIAL REGION:
Nose: Fully pigmented, and colour according to coat colour.
Lips: Close-fitting, firm and closed lip corners. Lip edges fully pigmented and colour according to coat colour.

Dark, colour according to colour of the coat. Medium sized, rounded, no exaggerated bulging and set wide apart. Lids tight-fitting and well pigmented.

Set at the back of the head, triangular, firm, naturally erected, carried in a gentle angle to the sides.

Jaws/Teeth: Firm and converging to muzzle. Regular scissor bite. A full dentition is preferred.

Neck without folds, gracefully curved and sufficiently long, at correct angle to body and head.

General appearance: Viewed from the front, straight and parallel legs, they should not stand too wide.
Shoulder: Muscular, laid back and close to the chest. Upper arm: Straight, muscular.
Elbow: Close to body and straight. Turned neither in nor out. Forearm: Adequately strong, straight.
Metacarpus (Pastern): Viewed from the front, a fluent continuing of forearm. Viewed from the side slightly inclined, strong.

Top line: Level and firm. Withers: Slightly visible. Back: Short, straight, firm. Loin: Short, well coupled.
Croup: Gently inclined, sufficiently long.
Chest: Oval in cross-section. Chest depth forms 45 – 50% of the height at the withers.
Underline and belly: Abdomen is slightly tucked up, between abdomen and loins clearly merging into drawn-in flanks.

General appearance: Muscular and enough angulated viewed from the side. Viewed from behind, the dog should stand solidly, legs parallel and not too wide apart.
Thigh: Adequately muscled.
Stifle joint (Knee): Well angulated. Lower thigh: Proportionally muscled. Hock joint: Well angulated.
Metatarsus (Rear pastern): Strong and straight.

Forefeet: Round, firm, with well arched, tight toes, nails dark.
Hind feet: Slightly oval, firm, arched tight toes. Nails dark.

Set at the level of back, sporadically docked in country of origin. If not docked, it should reach no further than the hock joint. Firm tail, it gets narrower to the tip.
The tail is straight half way up and carried slightly upright. When the dog moves it is carried higher, it can be curved over the back in a semicircle.

Balanced angulations in front and rear will produce steady, flowing, parallel, light movement. Pads must not drag along. Trot should be ground covering.

Skin is tough, strong, firm and fits tight to body. Pigment according to the colour of the coat.

Hair:
1) Short, glossy, fitting close to body, thick, without bald places. Head is usually coated with thinner and shorter coat than the body.
2) Moderately long, fringes on ears, quarters, tail and slightly longer on the chest.

Black, brown or blue with tan-markings including their dilutioned variations (in any shade, from very pale to very rich). Yellow recessive colour (with pale pigmentation) and red in most rich shades. These are without tan-markings. Black and tan merle and brown and tan merle.
Tan-markings are preferably a deep reddish tan, except in the blue varieties where it is paler according to the genetic make-up.
Tan-markings are found above the eyes, on cheeks, on chest and on the pasterns and feet, also at inner side of the hindquarters and under the root of the tail. On the fore chest it forms two similar and separated triangles.
Pigmentation on nose, eye- and lip-rims are according to coat-colour, but deeper pigmentation is preferred.

Height at the withers:
Males and females: 21–23cm (tolerance +/- 1cm)
Weight: Males and females: optimal approx 2.60 kg

Any departure from the foregoing points should be considered a fault and the seriousness with which the fault should be regarded should be in exact proportion to its degree and its effect upon the health and welfare of the dog.

• Long body with short legs.
• Narrow or insufficiently arched skull.
• De-pigmented nose.
• Asymmetrical bite.
• Missing incisor.
• Slightly arched back and loins, soft back.
• Permanently curled tail, or tail closely laying to one side, low-set tail.
• Feet slightly turning out or inwards.
• Excessive, not clearly defined tan-markings on head, abdomen and on the chest.
• Black hairs in the tan-colour.
• Big white spot on the chest (more than 1cm2).
• White spots on toes.
• The occurrence of blue color in eye up to 50% of the area for merle coloring.
• Size over 24cm or under 20cm.

DISQUALIFYING FAULTS:
• Aggressive or overly shy dogs.
• Any dog clearly showing physical or behavioural abnormalities.
• Open fontanel.
• Apple shaped head. Too short in muzzle.
• Overshot bite.
• More than 4 teeth missing (except P1 and M3), 2 or more incisors missing.
• Blue or predatory eye (very pale yellow).
• Hanging ears.
• Strongly arched back and loins (roached).
• Bald spots on any part of the body.
• Tan-marked dogs lacking tan-markings on the head.
• Large white mark on the chest, more than 2cm2 and white markings anywhere on body or legs.
• Excessive black overlay obscuring the tan-markings.
• The occurrence of blue color in eye over 50% of the area for merle coloring.
• Size over 26cm or under 18cm.

• Male animals should have two apparently normal testicles fully descended into the scrotum.
• Only functionally and clinically healthy dogs, with breed typical conformation should be used for breeding.