How Big Does a Jack Russell Terrier Get?

Jack Russell Terriers are clever little dogs beloved by hunters and outdoorsy people. They are known for their tiny bodies and high energy levels. 

But how big do Jack Russell Terriers get? We’ll dive into the Jack Russell Terrier breed, addressing how big they get and giving you plenty of other interesting facts about this curious breed. 

how big does a Jack Russell Terrier get
How big does a Jack Russell Terrier get?

What Is the Breed Standard for a Jack Russell Terrier? 

Like any other dog breed, the Jack Russell Terrier has a very particular set of traits that set it apart from other dog breeds. 

Size

To answer the main question first, Jack Russel Terriers can be anywhere from 13 to 17 lbs. Fully grown, they will be anywhere from 10 to 15 inches high

Some kennel club standards have slightly different classifications for the Jack Russell Terrier. The 10 to 15 inches fits within the Jack Russell Terrier Club of America. They choose to split Jack Russel Terriers into two height groups in their official category.

Group A is Terriers from 10 to 12 1/2 inches tall. Group B is those over 12 1/2 inches tall to 15 inches. 

However, if you look at the official American Kennel Club, they require Jack Russel Terriers to be between 12 and 14 inches

jack russell puppy
If you adopt a Jack Russell puppy, expect a ball of energy and lots of play

Coat

Jack Russell Terriers have a double coat. A double coat consists of an outer coat of coarse straight hairs and an inner coat of softer hairs. The inner coat helps to hold in heat, while the outer coat protects the dog from moisture reaching the skin. 

The coat is hard and flat, giving these Terriers a smooth appearance. There are three accepted coat types for Jack Russell Terriers, either rough, smooth, or broken. 

They are typically white, sometimes with black or tan markings. 

Despite being double coated, the hard and flat characteristics make these dogs very easy to groom and upkeep. 

Jack Russell Terrier petting
Petting Jack Russell Terrier by his owner.

Ears

The breed standard for ears is that they are floppy and folded over. In some cases, puppies may have ears sticking straight up. If this occurs, it may stop you from registering your dog with the local kennel club. 

There are ways to encourage their ears to flop, but there is no natural way to fix it if it occurs. The best way to make sure your dog stays within the breed standard for ears is to pay close attention to the puppy’s parents and see if they follow the breed standards. 

(Or, maybe you don’t care about breed standards, and you just love your puppy’s perky ears!) 

two Jack Russell Terriers together
Two Jack Russell Terriers posing together for a photoshoot.

Personality

Jack Russell Terriers are energetic dogs typically bred for hunting. They require at least 40 minutes of activity daily and carry a strong work ethic. 

These Terriers love to hunt and dig, so keep that in mind before you bring one home. Even small pets could be in their line of sight for hunting. 

Due to their hunting nature, they make excellent watchdogs. 

Jack Russell Terrier playing
Jack Russell Terrier running with a wooden stick in his mouth.

Who Are Jack Russell Terriers Best Suited For? 

Due to their natural hunting needs, Jack Russell Terriers are best for active owners who spend a lot of time outside. They require plenty of exercise, at least 40 minutes a day. These dogs make for excellent hunting or hiking companions!

They are naturally assertive, likely from their hunting instincts. The need to hunt is so strong in this breed that you can’t train it out of them. With that in mind, they’re not particularly good to have near hamsters or even small cats. 

Jack Russell Terriers are not the best dog for young children, either. They are also not always the best option if you have other dogs in the house (though each dog is different, so this isn’t a guarantee).  

These traits make Jack Russell Terriers great as a solo pet, preferably with a couple or a single individual. If you plan to adopt this breed with children, then wait until your children are a little older first. 

Jack Russell Terrier nibbles ear
Jack Russell Terrier puppy nibbles the owner’s ear while playing.

How to Groom a Jack Russell Terrier?

Jack Russell Terriers have a hard, flat coat of short hair. Due to this, they don’t often need grooming. Ideally, you should groom them twice a year.

Groom them once in February so that in spring, their coat has returned to its natural fullness. The double coat will help keep them cool in the summer. 

Groom them again in August. August grooming means having a full coat by winter to keep them warm in the snow. If you happen to use your Jack Russell Terrier in shows or competitions, those usually occur in October. August grooming will mean the coat will be back to its natural appearance in time for showings. 

For double-coated dogs, it’s usually not recommended to cut the fur. Instead, it is recommended to pluck or pull too long hairs. Complete this step after the initial brush out. 

It is recommended only to remove enough hair to make them look tidy when it comes to their face. 

While you’re grooming your dog, it is also an excellent time to clean out their ears. 

You should brush your Jack Russell Terrier about once a week between groomings. You can do this with a standard brush. You may need to brush them a little more often in the spring when they are shedding for their summer coat!

grooming Jack Russell Terrier
Jack Russell Terrier being groomed in a pet salon.

Frequently Asked Questions

Finally, check the FAQ below for commonly asked questions regarding Jack Russell Terriers for would-be owners. 

Can I keep a Jack Russell Terrier in an apartment? 

Jack Russell Terriers are very energetic dogs that need plenty of exercise. Unless you can devote an hour a day to ensuring your dog can go outside and work off some steam, they likely would not be thrilled. 

If you want a Jack Russell Terrier, it’s recommended that you have a house with a yard. It is preferable to have a fenced yard with a high fence. These little dogs are excellent jumpers and diggers, so keep that in mind before you let them outside!

Jack Russell Terrier licking
Jack Russell Terrier licking owner’s hand.

Will a Jack Russell Terrier get along with other pets? 

In general, no. Jack Russell Terriers will attempt to hunt anything smaller than them, such as hamsters, small cats, rabbits, etc. They tend not to get along well with other dogs either. 

Two Terriers should not be left alone together because they are prone to fighting. Even young puppies should be kept apart after eight weeks to keep them from hurting each other. 

One animal you will have luck with is horses. Raised as hunting dogs, Jack Russell Terriers are practically bred to be comfortable with horses. They will not try to herd them and will generally leave horses alone.

Are Jack Russell Terriers good with children? 

Not young children. Jack Russell Terriers are naturally assertive and do not put up with young children very well. If you have children and still want this breed, it is highly recommended that you wait until your children are at least over the age of six before you adopt. 

Jack Russell Terrier with a boy
A boy spends time playing with his Jack Russell Terrier.

Do Jack Russell Terriers have any common medical issues? 

Jack Russells are a breed that don’t come with many health issues. You will only need to keep an eye out for the same problems that plague all breeds of dogs. 

Some common ones that might pop up include teeth and gums issues, ear infections, obesity, arthritis, and aggressiveness

As with any dog breed, regular checkups with your vet and staying up to date with vaccinations will help your Jack Russell live a whole and healthy life (thought they are velcro dogs that will follow you everywhere)

Do I need to register my dog with a kennel club? 

No. That step is entirely up to you. If you are purchasing a puppy from a reputable breeder, it’s possible your dog was registered with a kennel club from the moment of its birth. 

Registration is only essential if you are planning on entering your dog into shows or competitions. A kennel club registration also acts as a form of proof from the breeder that your dog is purebred if that detail is essential to you. 

Jack Russell Terrier with bowl of food
A Jack Russell Terrier looking at the camera with his food.

Final Thoughts

Jack Russells are adorable dogs that make wonderful companions for hunters and active people alike. They are inquisitive creatures with a happy disposition. Aside from needing an active lifestyle, they are a very low-maintenance breed that only needs to be groomed twice a year and brushed once a week. 

They are relatively compact dogs, too, only coming to 15 inches high at maximum. They’re a lot of personality in a small package. That may not be the best dog for all people, but they are excellent for those who can meet their needs.