St. Bernard weight chart by age
In a published growth study, adult St. Bernard dogs averaged about 144 lb (65.2 kg). Puppies reached 99 percent of that weight at around 57 weeks, which is about 13 months. Use the chart to see what is typical at each age, or enter your puppy's weight for an estimate of the adult size.
Your puppy is at about 31% of its adult weight.
St. Bernard puppy weight by age
| Age | Pounds | Kilograms | Of adult weight |
|---|---|---|---|
| 8 weeks | 19.8 | 9.0 | 14% |
| 12 weeks | 30.6 | 13.9 | 21% |
| 16 weeks | 45.2 | 20.5 | 31% |
| 20 weeks | 62.9 | 28.5 | 44% |
| 24 weeks | 81.8 | 37.1 | 57% |
| 32 weeks | 113.8 | 51.6 | 79% |
| 40 weeks | 131.7 | 59.7 | 92% |
| 1 year | 141.1 | 64.0 | 98% |
| 15 months | 143.3 | 65.0 | 100% |
| 18 months | 143.7 | 65.2 | 100% |
| Adult average | 143.7 | 65.2 | 100% |
Values are calculated from the growth curve fitted to the St. Bernard puppies in the study. Males and females were not reported separately here, and individual dogs vary, so treat the numbers as a typical pattern, not a standard.
St. Bernard growth chart
The dot marks one year. After that, weight changes slowly.
How fast does a St. Bernard grow?
This breed is in the giant group in our puppy size calculator. Growth was half done at about 22 weeks, which is when the curve is steepest. A St. Bernard is usually close to its adult weight by 13 months, although the body can keep filling out afterward. For how much to feed along the way, see the puppy feeding chart.
Questions
How much should a St. Bernard puppy weigh at 8 weeks?
In the study a St. Bernard weighed about 19.8 lb (9.0 kg) at 8 weeks.
How much should a St. Bernard puppy weigh at 16 weeks?
About 45.2 lb (20.5 kg), which is roughly 31 percent of the adult weight.
How much does an adult St. Bernard weigh?
The adult dogs in the study averaged about 144 lb (65.2 kg). Breed standards and individual dogs differ.
When is a St. Bernard fully grown?
Around 57 weeks (13 months) for weight, according to the growth curve.
Is my St. Bernard overweight?
Weight alone cannot say. Use the body condition check to look at ribs and waist.
Other breeds
Papillon, Cocker Spaniel, Miniature Schnauzer, Cairn Terrier, Beagle, English Springer Spaniel, Labrador Retriever, English Mastiff, Irish Wolfhound, Great Dane, Newfoundland. See also the dog weight chart for all breeds side by side.
Sources
- Hawthorne A.J. et al., "Body-weight changes during growth in puppies of different breeds", Journal of Nutrition, 2004.
Last reviewed 2026-10-26. This page is general information and not veterinary advice.