Also known as the pražský krysařík, and often confused with the Chihuahua and the Miniature Pinscher, the dog's coat consists of short, glossy hair and the most common color is black and tan, which is also the original color. Lately, other colors have been approved: brown and tan, blue and tan, lilac and tan, yellow, red and merle. It is 2 cm shorter in maximum height than the minimum height of the Miniature Pinscher.
Best known for its active and lively nature, the Prague Ratter is a spunky breed that is full of original character. These tiny dogs thrive on strong and dependable relationships with humans, love to receive affection and play the role of lap dog during down time. This breed is highly intelligent and generally responds well to basic training and commands. As a pet, the Prague Ratter is obedient, loyal, loving, and very affectionate. The Prague Ratter adapts well to full-time indoor and apartment living, yet still enjoys spending time outdoors, playing games such as fetch, and taking long and leisurely walks. They are also known to be a very quiet dog unlike many other small dogs who tend to be very "yappy". Like any small dog one should be wary of allowing them to develop Small Dog Syndrome as they can become aggressive if they are allowed to become dominant over their owners.Ideal height is 20 cm to 23 cm. Adult weight is mostly between 1.5 kg to 3.5 kg. Generally the best weight is 2.6 kg.