General Appearance

The Bullmastiff is a large, powerful, and symmetrical dog, giving the impression of great strength without bulkiness. Its appearance is a perfect blend of agility and power, with an alert and confident demeanor. The body is compact and solidly built, conveying a balanced and courageous guardian.

​

Size, Proportion, Substance

• Height:

  • Males: 25–27 inches (at the withers)

  • Females: 24–26 inches

• Weight:

  • Males: 110–130 pounds

  • Females: 100–120 pounds

• Proportion: The body should be slightly longer than tall with a deep chest and level topline.

• Substance: Massive, muscular, and powerful without appearing clumsy.

Head

• Expression: Keen, alert, and intelligent.

• Skull: Large, broad, and slightly wrinkled when alert.

• Forehead: Flat with a moderate stop.

• Muzzle: Broad and deep, roughly one-third the length of the head.

• Nose: Black with wide nostrils.

• Bite: Slight undershot bite preferred; level bite acceptable.

• Eyes: Dark and medium-sized, set apart with an alert expression.

• Ears: V-shaped, set high and wide apart, lying close to the cheeks. Darker in color than the body.

Neck, Topline, Body

• Neck: Well-arched, muscular, and of moderate length, blending smoothly into the shoulders.

• Topline: Straight and level from withers to loin.

• Back: Short and strong.

• Chest: Broad and deep, with well-sprung ribs extending well back.

• Flank: Slightly tucked up.

• Tail: Set high, strong at the base, tapering to the hock. May be straight or curved like a sickle.

Forequarters

• Shoulders: Muscular and sloping.

• Forelegs: Straight and heavy-boned, set well apart to support a broad chest.

• Pasterns: Strong and slightly sloping.

• Feet: Compact and cat-like with well-arched toes and thick pads.

Hindquarters

• Thighs: Broad and muscular.

• Stifles: Well bent.

• Hocks: Well let down, straight and parallel when viewed from the rear.

• Feet: Same as the front, with strong, compact structure.

Coat

• Texture: Short and dense, giving good protection against weather and terrain.

• Color: Red, fawn, or brindle. A small white marking on the chest is permissible.

• Mask: Black mask essential, blending into the ears and muzzle.

Gait / Movement

Movement should be free, powerful, and effortless. The Bullmastiff should cover ground with purpose and drive, with a strong, balanced, and fluid gait. The legs should move straight and true, showing no signs of crossing or rolling.

Temperament

The Bullmastiff is brave, confident, and extremely loyal. Though protective, it is not aggressive without reason. This breed is naturally reserved with strangers but gentle and affectionate with its family. Bullmastiffs make excellent family guardians when properly socialized and trained.

• Disposition: Calm, courageous, and affectionate

• Training: Needs consistent, firm, yet gentle training from an early age

• Socialization: Critical to ensure a well-rounded temperament

Faults

• Shyness or excessive aggression

• Lack of substance or balance

• Overly long body or roached back

• Light eyes or poor pigmentation

• Cow hocks or unbalanced gait

Disqualifications

• Blue eyes

• Albinism

• Extreme deviation from accepted size and structure

• Aggression without provocation or excessive shyness

 

Ideal Owner

Bullmastiffs thrive with confident owners who can provide consistent leadership, training, and socialization. Their calm demeanor indoors makes them excellent family companions, but they require regular physical and mental stimulation.

​

The Bullmastiff is a breed with one of the most precisely documented working origins in dog history. In the mid-19th century, English gamekeepers faced a serious problem: poachers killed or maimed gamekeepers who confronted them, and the dogs available at the time were either too aggressive (killing poachers, creating legal liability) or too small to physically restrain them. Gamekeepers began systematically crossing the English Mastiff with the English Bulldog in a documented ratio of approximately 60% Mastiff to 40% Bulldog — the Mastiff providing size, strength, and tracking ability, the Bulldog providing the silent, determined, and fearless quality needed to work at night. The result was the "Gamekeeper's Night Dog" — a dog that could silently track a poacher across a dark estate, knock them down, and hold them without killing them until the gamekeeper arrived. The UK Kennel Club recognized the Bullmastiff as a distinct breed in 1924, and the American Kennel Club followed in 1933. Today, WowPooch (February 2026) documents 30 confirmed Bullmastiff mixed breeds. Designer Kennel Club registers both purebred Bullmastiffs and every Bullmastiff mix. WowPooch

​

The most popular Bullmastiff designer crosses include the Bull Doodle (also known as the Mastidoodle or Bullmastidoodle — Bullmastiff × Poodle, documented by dogbible.com and floofydoodles.com), the Bullmasador (Bullmastiff × Labrador Retriever — confirmed by Animal Corner (April 2026) as a devoted family watchdog), the Bullkita (Bullmastiff × Akita — WowPooch February 2026), the Bull Daniff (Bullmastiff × Great Dane), the Bull Pei (Bullmastiff × Shar-Pei), and the Bull Basset (Bullmastiff × Basset Hound). The AKC registers purebred Bullmastiffs — but AKC cannot and does not register any Bullmastiff mix regardless of generation. Designer Kennel Club was built for exactly this gap. Animal CornerWowPooch

​

Designer Kennel Club provides official registration papers for purebred Bullmastiffs, Bull Doodles, Mastidoodles, Bullmastidoodles, Bullmasadors, Bullkitas, Bull Daniffs, Bull Peis, Bull Bassets, and all other Bullmastiff crosses with no AKC papers or pedigree lineage required. DKC Foundation Dog Registration ($65) accepts any Bullmastiff or Bullmastiff mix without existing documentation. Bullmastiff owners who need official breed documentation for housing requirements, HOA compliance, or rental agreements where Bullmastiffs face breed restrictions will find DKC registration provides exactly this documentation. For breeders, DKC Litter Registration ($100) gives each puppy an individual DKC registration number that new owners can use to register for $45. Papers are delivered as a PDF via email within 2–3 business days.

​

Whether you are registering a purebred Bullmastiff or a first-generation Bull Doodle or Bullmasador you bred yourself, Designer Kennel Club provides official breed and ownership documentation accepted for veterinary records, grooming services, training programs, housing requirements, and general ownership verification. Register at designerkennelclub.com/registration.