Great Dane vs Mastiff

Both breeds are giants with short coats, and both stand at least about 30 inches for males. At a distance they can look alike, especially in fawn. The differences are in proportion and color: the Great Dane is a square, elegant dog, while the Mastiff is massive, broad and heavy-boned.

The weight gap is real. Vets list Great Danes at about 110 to 175 pounds, and Mastiffs at 175 to 190 pounds. Great Danes also have a shorter typical lifespan, 7 to 10 years against 9 to 11, and a higher risk of bloat. Mastiffs are drooly, calm and prone to gaining weight, so their care needs differ.

Great Dane vs Mastiff side by side

Last verified October 2026. Typical values; individual animals, products and local prices vary.

When you are looking at which

Great Dane

• The dog is harlequin, blue, black or mantle-patterned, colors a Mastiff cannot have.
• The outline is tall and square, with a long, rectangular head and an elegant neck.
• The dog weighs 110 to 175 pounds, with clean, athletic lines.
• The head is long and rectangular on a tall, square body.

Mastiff

• The coat is silver fawn, dark fawn-brindle or apricot, with a black muzzle, ears and nose.
• The dog looks heavy, broad and thick, with a massive head and deep chest.
• The dog weighs 175 pounds or more, and drool is part of daily life.
• The dog is calm, loyal and a little aloof with strangers.

How this works

The quiz asks about color, face, weight, build and head shape. Each answer points to Great Dane or Mastiff, and each cue line says how reliable the clue is. Harlequin, blue or a missing black mask rules out a Mastiff, and it counts for the most.

Many Mastiff and Great Dane crosses exist, and they can break the pattern. Weight ranges also overlap at the high end, so use size as supporting evidence only. For a pedigree answer, ask the owner for registration papers from a kennel club.

Where these numbers come from

The figures and defaults on this page are based on:

• United Kennel Club: Great Dane, Great Dane height, colors, ears, build and temperament. (checked October 2026)
• United Kennel Club: Mastiff, Mastiff height, colors, black mask requirement and temperament. (checked October 2026)
• VCA Animal Hospitals: Great Dane, Great Dane weight, height, lifespan and health risks. (checked October 2026)
• VCA Animal Hospitals: Mastiff, Mastiff weight, height, lifespan, drool and weight tendency. (checked October 2026)

Breed-identification guide. Individual dogs vary and mixed breeds cannot be confirmed by appearance.