How big do Tibetan Mastiffs get? The tool below projects your own puppy’s adult weight from its current age and weight, plotted against the typical Tibetan Mastiff growth curve.
Estimates combine your puppy’s current trajectory with typical growth curves for this breed and size class. Individual dogs vary — nutrition, genetics and neuter timing all matter. For health concerns, ask your vet.
The Tibetan Mastiff is a giant breed. Adult males typically weigh 90–150 lb (40.8–68.0 kg) and females 70–120 lb (31.8–54.4 kg). Most Tibetan Mastiffs reach about half their adult weight around 5.0 months, hit 90% by roughly 12.2 months, and are fully grown near 20 months. Giant breeds grow longer than any other dogs — some don’t reach full size until age two.
When do Tibetan Mastiffs stop growing?
Most Tibetan Mastiffs reach their full adult height and weight by about 20 months. Growth is fastest before 5.0 months, then slows steadily — by 12.2 months your puppy will be about 90% of its final size.
How much should a Tibetan Mastiff puppy weigh at 4 months?
A typical 4-month-old Tibetan Mastiff weighs roughly 33–55 lb, about 41% of its adult weight. Use the calculator above with your puppy’s exact weight for a personalized estimate — individual dogs vary.