Schnauzers come in three sizes: giant, standard and miniature. Their small size makes the miniature the most popular choice. When people moved from farms to smaller homes because of the Industrial Revolution, they wanted a schnauzer to fit in those homes. According to the Encyclopedia of Dog Breeds, the miniature schnauzer was the result of crossing standard schnauzers, affenpinschers, miniature pinschers and perhaps poodles.
In order to win in dog shows, a miniature schnauzer must stand 12 to 14 inches tall and weigh no more than 6.8 Kilogram. Not all purebred miniature schnauzers meet this breed standard.
Because their ancestors were standard schnauzers, which grow to 17 to 19.5 inches tall, it is theoretically possible for a miniature schnauzer to grow taller and heavier than the breed standard.
Although there are many dogs for sale advertised as teacup miniature schnauzers, there is no such breed and they cannot be registered or shown.
According to the ASPCA Complete Guide to Dogs, although miniature schnauzers are small enough to live in apartments, they still need a long walk every day to burn off excess energy.
Many small dog breeds live longer than larger dogs, and the miniature schnauzer is no exception. While the giant schnauzer has an average life expectancy of 10 to 12 years, the miniature schnauzer can live 12 to 15 years.