This is an easy one to answer because we have a Guinness World Record on this topic and the smallest cat on record was a male blue point Himalayan (pointed Persian) whose name was Tinker Toy. When fully grown he measured 2.75 inches (7 cm) tall and 7.5 inches (19 cm) long at the age of 2.5 years. He was owned by Katrina and Scott Forbes of Taylor Mill, Illinois, USA. He was born on December 25, 1990 and was the runt of six kittens in one litter and died in November 1997 at the age of six. His weight is not on record but was probably around 3 pounds.
There are no photographs which for a lot of people is a shame because they really want to see this miniature domestic cat. Below is a photo of a miniature cat.
There was a time when some breeders (rarely) bred miniature cats and they were usually Chinchilla Persians. They were selectively bred but the problem as I recall is that they had health problems and therefore the concept of owning a miniature cat which had been deliberately created fell out of favour.
One such cattery now closed was Pocket Kittys. I believe it was closed in 2012. This was the time when dwarf cats were also popular but they too have fallen out of favour because of health problems. These deliberately bred miniature cats weighed in the region of 3-6 pounds. They were referred to as Teacup cats.
They would have been selectively bred from cats like Tinker Toy. The smallest cat breed is the Singapura and the smallest naturally occurring cat of all, either wild or domestic is the rusty-spotted cat. The weight of this diminutive wild cat is similar to that of miniature cats. For females that is 1 kg or 2.2 pounds and on average it is 1.5 kg or 3.3 pounds.
The rusty-spotted cat has a head plus body length of 14-17 inches (35-48 cm). This is considerably longer than Tinker Toy. This may partly be because Tinker Toy was probably a flat-faced contemporary type Himalayan. These cats are what I call ‘cobby’ meaning short in length.
Below are some more pages on world records.
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