Most miniature schnauzer dogs are full grown by 12 months of age or 1 year of age and stop growing after a year old.
However some miniature schnauzers may continue to grow a little bit until 14 months of age but usually by 12 months of age most miniature schnauzers are no longer growing.
By the time the mini schnauzer is 6 months of age they will be between 75 and 85 percent of their full grown weight and by 12 months they are usually at their full grown weight and height.
When a Miniature Schnauzer is between 8 to 10 months of age they are usually 12 and 13 pounds in weight which is their normal weight and then by the time they are fully grown they may weight from 18 lbs to 20 lbs.
Male Miniature Schnauzer dogs typically weigh a bit more than the female Miniature Schnauzer dogs.