A teacup yorkie is a small version of a Yorkshire terrier. A teacup yorkie weighs 2–4 lbs (0.9–1.8 kg), significantly smaller than a regular yorkie, which weighs 6–7 lbs (2.7–3.2 kg).
Teacup yorkies and Yorkshire terriers are not separate breeds; traditional yorkies are just selectively bred to become even tinier, producing the teacup yorkie. This is why they’re often referred to as designer dogs.
Aside from their size, there are other notable differences between a teacup yorkie and a Yorkshire terrier. For example, a teacup yorkie is usually more playful and harder to train. It also requires more care, as its size makes it prone to birth defects, injuries, and health problems.