Miniature Jack Russell dogs grow to be smaller than 10 to 15 inches and less than 14 to 18 pounds. Miniature Jack Russell terriers are smaller than their full-sized counterparts.
According to the Dog Breed Info Center, the temperament and needs of the miniature Jack Russell terrier are the same as its larger counterpart. These are very energetic dogs that require a lot of exercise. They do not take up a lot of space, so they are a good choice for people who live in an apartment. They are prone to mast cell tumors, joint issues, deafness and eye conditions.
There is no such thing as a miniature Jack Russel. They are small dogs as it is, so if you have been sold a "miniature" it is the runt of the litter, which is why it is
My 2 and a half months old JRT is very small, she is 800g. People often ask if she is a Chifuafua.