Summer’s best deal: Over 30% off pet DNA tests.

Shop Now
Blog /Guard Dogs Come In All Shapes And Sizes
Breed and Genetics September 22, 2023

Guard dogs come in all shapes and sizes

These fast-learning, loyal dogs make excellent protectors and solid family companions.

For centuries, dogs have protected people and property from unwanted intruders and served as an extra set of eyes and ears for their pet parents. Though Guard Dog is a genetic breed group, other protective and watchful dogs fall outside of that group. Let’s look at some common breeds that fall into both categories.

Characteristics of guard dog breeds

First and foremost, a good Guard dog has an instinct to protect their home. They can be territorial, and many are wary of strangers. Though some may have dominant personalities, they should not be highly aggressive. Guard dogs are also naturally alert, watchful, and loyal to their people. They are typically courageous and strong, with loud barks that let intruders know they’re there. But they are also very responsive to their pet parents. Guard dogs have an intense eagerness to please and an obedient nature.

Three Bull Terriers sitting on a lawn.

Small guard dog breeds

You may be surprised that not all guard dogs have a large, imposing presence. These pups pack a lot of strength and bravery into a small (and charismatic) package.

Boston Terrier

Boston Terriers are sturdy, muscular dogs. Originally bred for dogfighting, these little dogs are now known as "the American gentleman" due to their affectionate and friendly personalities. 

Miniature Bull Terrier

Miniature Bull Terriers are strong, brave dogs but have a silly side, too. They usually become very attached to their people and are gentle with their family and kids.

French Bulldog

French Bulldogs are well-behaved and easygoing. They’re very people-oriented dogs and love being the center of attention. Frenchies will stick up for their families—usually by issuing a warning growl—if they perceive a threat from a strange dog.

Boxer lying outside in the grass.

Popular medium-sized guard dog breeds

These mid-sized pups are not only excellent guard dogs but also make outstanding family pets.

American Staffordshire Terrier

American Staffordshire Terriers are loyal to their families and can be protective if necessary. They’re courageous and powerful dogs that are gentle and loving at heart. These loyal pups are usually good with kids and can make fun-loving pets.


Over the years, Bulldogs have developed into sweet, dignified dogs that are gentle and affectionate with their families. They’re eager to please and happy to curl up into their human’s lap. However, they can sometimes be suspicious of unfamiliar dogs.


Boxers are hardworking, intelligent dogs that have performed various jobs over the years (including circus dog!). These upbeat, playful dogs are loyal to their people and make excellent family guardians.

Black and white Great Dane standing outside in a park.

Well-known large Guard dog breeds

When people think of guard dogs, these breeds most commonly come to mind.


Mastiffs are brave, protective dogs with patient and calm demeanors. At 200 lbs, they can appear intimidating, but Mastiffs are softies at heart. They have loving personalities and are usually good with kids.

Doberman Pinscher

Doberman Pinschers are fearless, intelligent dogs. They’re fiercely loyal to their families and protective of their people and homes. Because of their good-natured, affectionate personalities, they frequently work as guide and therapy dogs.


The Rottweiler is a strong, trustworthy, and hardworking breed. They’ve worked as military and police dogs but perform just as admirably as loving companions and gentle household pets. 

Cane Corso

The Cane Corso’s even temper, loyal nature, and trainability make them excellent guard dogs. Though trustworthy family members who are usually gentle with children, they can respond defensively to other dogs if provoked. 

Great Dane

Great Danes are famous for their massive size, but their goofy personalities and gentle natures deserve just as much attention. These dogs are very loyal and form close bonds with their people. Just make sure you have a (really, really) big couch; Danes will happily climb up for a cuddle session.

Black and brown Dachshund standing at the bottom of a staircase.

Other protective dogs and watchdogs

Even though they aren’t part of the Guard Dog genetic group, plenty of other dog breeds—and mixed breeds, too— have a protective, vigilant nature. Here are a few dog breeds you can likely count on to keep an eye on your family and your home.


Dachshunds make excellent watchdogs. These vigilant pups are suspicious of strangers and very protective of their people and homes. The Dachshund family includes several varieties and sizes: shorthaired, longhaired, wirehaired, miniature shorthaired, miniature longhaired, and miniature wirehaired. 


Miniature Schnauzers and Giant Schnauzers also fall into the watchdog category. These tenacious terriers are extremely alert and tend to be wary of people they don’t know. They’re also an eager-to-please breed that’s entirely devoted to their people. 

Karelian Bear Dog

The Karelian Bear Dog is an energetic breed best suited for life in the country. They’re intelligent dogs with a protective nature. Though they can be very territorial, they aren’t aggressive with people. 

Thai Ridgeback

Thai Ridgebacks are independent, self-sufficient dogs that are hunters at heart. Though not overly affectionate, they do form bonds with their families and want to protect them.

German Shepherd Dog

German Shepherds are all-purpose working dogs devoted to their families and known to have a watchful nature. If an unknown person wanders near your home, there’s a good chance your German Shepherd will bark and let you know.

Find the breed that’s right for you

Whether you’re looking for a fearless protector or a high-energy hiking buddy, the more you know about a breed, the better. Browse our breed library to find the perfect fit for your pack.