FCI Group 9 · FCI #363 · Purebred · The world's smallest dog by body size — Czech royalty's elegant bat-eared ratter with a spirited soul
The Prague Ratter — known in Czech as the Pražský Krysařík — holds a unique distinction: it is considered the smallest dog breed in the world by body size, with adults typically weighing between 2 and 6 pounds and standing just 7–9 inches tall. Despite its minute stature, this is a lively, athletic, and surprisingly confident dog that was bred to hunt and kill rats, not merely to sit on a lap.
Originating in medieval Bohemia (now the Czech Republic), the Prague Ratter was the favored companion of Central European royalty for centuries. Polish and Bohemian kings kept them in their courts, and the breed was so prized that it was gifted among rulers as a diplomatic token. After nearly disappearing in the 20th century, dedicated Czech breeders revived the breed. It was officially recognized by the FCI in 2019 as breed #363, making it one of the newest FCI-recognized breeds in the world.
Real Prague Ratters — browse photos showcasing their look, size, and personality.
The Prague Ratter is a bold, alert, and surprisingly energetic dog that defies its tiny size at every turn. It is affectionate with its family but typically reserved with strangers — a natural watchdog. Despite its history as a ratter, it integrates well into modern home life when properly socialized.
Despite its tiny size, the Prague Ratter has genuine energy and needs daily exercise to stay healthy and mentally balanced. It is surprisingly athletic for its size and enjoys running, playing, and exploring.
The Prague Ratter has a short, smooth, close-lying coat that requires almost no grooming — one of its most practical advantages as a companion dog.
Prague Ratters are intelligent and eager to engage with their owners, making them more trainable than many toy breeds. However, their independent streak and small size mean consistent, patient handling is essential — "small dog syndrome" is a real risk if boundaries are not set early.
The Prague Ratter is generally a hardy breed for its size, but its extreme smallness brings specific vulnerabilities. Responsible breeders screen breeding stock carefully.
The Prague Ratter suits individuals or couples who want an exceptionally small, lively companion. Its fragility makes it less suitable for households with young children or large boisterous dogs. It thrives with attentive owners who can provide warmth, consistent companionship, and gentle handling.
Feeding a Prague Ratter requires extra care — their tiny stomachs and high metabolism make them prone to hypoglycemia if meals are skipped. Feed small, frequent meals and never let puppies go more than 4 hours without food.
The Prague Ratter is very rare outside of Central Europe. Most puppies available in North America are imported or from a small number of specialty breeders. Expect significant cost and waiting lists.
Despite the high acquisition cost, day-to-day expenses are low due to the dog's tiny size. Expect $60–$130 per month on average.
Over a 12–14 year lifespan, a Prague Ratter typically costs between $7,000–$16,000 total — largely driven by the purchase price and any dental or orthopedic care needed.