The Welsh Terrier is colored tan on the head, legs and underbelly while having a black or sometimes grizzle saddle. The breed is a sturdy and compact dog of about medium size that can grow up to 15.5 in. (39.5 cm) with a weight of 20-22 lbs (9–10 kg). The tail is usually docked and is more preferred in order to complete the image of a square dog that is as tall as it is long. The body shape is rectangular, with elongated, "brick-like" face. This shape is formed by the whiskers and beard.
The Welsh Terrier is a consummate terrier—a terrier in a nutshell—with a typical terrier temper. In the right hands, it is a happy, lively, and seldom shy or timid dog, but sometimes can have an attitude. Dogs of this breed can be devoted friends and can function either as city dogs or as country dogs. Welsh typically exhibit a hunting instinct: they chase anything that moves: dry leaves, cats, mailmen, other animals, tumbleweeds, small children, almost anything.
Welsh Terriers were developed to hunt independently and this required that they be very assertive and stoic dogs. As a consequence, developing obedience in a Welsh Terrier is a long term proposition and one has to convince the dog that the owner is the alpha male. Application of physical force should be done only in the extreme situations as Welsh Terriers, like most terriers, will not back down and will fight back. A quiet but persistent approach to ensure that Welsh Terrier in the end completes the command, in the end will establish who is in control.
A Welsh Terrier is full of energy and it hardly ever becomes tired. Letting a Welsh Terrier have a run around the yard during the day is insufficient. If bored, they may explore and potentially cause mischief and damage. You need to challenge them and keep them entertained. For example, they love chasing toys to keep active and love swimming (a good example would be lake activities with their families).
Welsh Terriers get along well with older children; they love to play and follow a child as it plays, however, they will often tug at pant legs of young and old people and can knock young ones off their feet. If they are around young children at an early age, they will easily learn to play more gently.
The body of the Welsh Terrier is normal and healthy so that the physique is durable and lasting. Some studies have suggested a genetic predisposition to Glaucoma, as yet inconclusive . A healthy Welsh Terrier lives about 12–13 years on average and stays active and alert up to a high age if it is well taken care of and healthy.
