Canis lupus familiaris
Prague Ratter
Featured photoprague-ratter.jpgThe Prague Ratter is a tiny, smooth-coated Czech companion and working dog considered by many authorities to be the smallest dog breed in the world by standard measurements, smaller than the Chihuahua in the FCI system. The breed was the court dog of the Bohemian kingdom from the early medieval period and was used to control vermin in royal apartments. The FCI registered it as No. 363 in 2019 under Czech and Slovak patronage. Males stand under 20 cm.
Quick facts
- AKC group
- Toy
- Origin country
- Czech Republic
- Origin period
- Medieval, revived 20th century
- Coat type
- Short
- Coat colors
- Black and Tan, Brown and Tan, Blue and Tan, Lilac and Tan, Yellow, Red, Merle patterns
- Average lifespan
- 12-14 years
- Recognition
- FCI 2019 · Group 9 — Companion and Toy Dogs (Section 7: Companion and Toy Dogs)
Origin
The Prague Ratter is one of the few dog breeds whose origins are documented through medieval Bohemian court records. The breed is mentioned in accounts of the Přemyslid dynasty (which ruled Bohemia 870–1306), where small, smooth-coated dogs were kept in royal chambers to control mice and rats. The breed was subsequently popular at the courts of Poland, Hungary, and other Central European kingdoms as a portable lap companion and working ratter. Later Polish sources credit the Prague Ratter as an ancestor of the Miniature Pinscher.
Recognition
The Czech-Moravian Cynological Union (ČMKU) registered the breed in 1980 after revival efforts located surviving specimens in rural Czech and Slovak communities. Czech and Slovak breeders submitted documentation to the FCI; provisional recognition was granted in 2019 under standard No. 363, placing the breed in Group 9, Section 7 (Companion and Toy Dogs) with the Czech Republic and Slovakia as joint patron countries. The breed is not currently recognised by the AKC or UKC.
Standard
The FCI standard describes an extremely small, elegant, lightly built dog with a wedge-shaped head, large upright ears, and a very short, smooth, glossy coat. The standard maximum height is 23 cm, with the ideal stated as 20–22 cm — placing the Prague Ratter below the Chihuahua's standard measurement and making it the smallest breed by FCI standards. Recognised colours include black and tan, brown and tan, blue and tan, lilac and tan, yellow, red, and various merle patterns. Males weigh 1.5–3.5 kg.
Sources & further reading (3)
- fci-standard — accessed 2026-05-27
- encyclopedia — accessed 2026-05-27
- kennel-club-registry — accessed 2026-05-27
Frequently asked questions
Is the Prague Ratter the smallest dog breed in the world?
By FCI breed standard measurements, the Prague Ratter is the smallest breed recognised by the FCI, with a maximum standard height of 23 cm. The Chihuahua, by comparison, is standardised at up to 30 cm in FCI measurements. Individual Chihuahuas may weigh less, and the record for the world's smallest individual dog typically belongs to individual Chihuahuas. The Prague Ratter holds the distinction for the smallest breed standard.
When was the Prague Ratter recognised by the FCI?
The FCI granted the Prague Ratter provisional recognition in 2019 under standard No. 363, with the Czech Republic and Slovakia as joint patron countries. The Czech-Moravian Cynological Union had registered the breed nationally in 1980 after revival efforts in the late 1970s. The breed is not currently recognised by the AKC or UKC.
What historical role did the Prague Ratter play at the Bohemian court?
At the Bohemian royal court from at least the 10th century, the Prague Ratter served as both a lap companion and a working ratter in the stone corridors, storerooms, and apartments of royal castles. The breed's small size allowed it to access the narrow gaps in medieval stone construction where mice and rats denned. It was also given as a diplomatic gift between Central European courts, spreading to the Polish, Hungarian, and later Austrian imperial court.
