Age when puppies stop growing, by size
| Size class | Adult weight | Example breeds | Close to full grown |
|---|---|---|---|
| Toy | up to 12 lb | Chihuahua, Yorkshire Terrier, Pomeranian, Maltese | 9–10 months |
| Small | 12–25 lb | Dachshund, French Bulldog, Shih Tzu, Miniature Schnauzer | 10–12 months |
| Medium | 25–50 lb | Beagle, Border Collie, Australian Shepherd, Siberian Husky | 12–15 months |
| Large | 50–100 lb | Labrador, Golden Retriever, German Shepherd, Boxer | 15–18 months |
| Giant | over 100 lb | Great Dane, Mastiff, Newfoundland, Great Pyrenees | 18–24 months |
"Close to full grown" here means the puppy has reached about 98% of its adult weight on the typical growth curve for its size. The curves are simplified from the growth standards published by Salt and colleagues in 2017, the same data our puppy weight calculator uses. The American Kennel Club gives similar ages: small breeds stop growing at about 6 to 8 months, medium breeds reach adult size at about 12 months, giant breeds keep growing until 12 to 18 months, and very large breeds such as Mastiffs may need up to 24 months.
Puppy growth chart: share of adult weight by age
How much of its final weight a typical puppy has reached at each age. To turn it into pounds, multiply by the expected adult weight; the calculator does this for you from your puppy's current age and weight.
| Age | Toy | Small | Medium | Large | Giant |
|---|---|---|---|---|---|
| 2 months (9 weeks) | 33% | 28% | 22% | 18% | 14% |
| 3 months (13 weeks) | 48% | 43% | 36% | 30% | 23% |
| 4 months (17 weeks) | 62% | 57% | 49% | 41% | 33% |
| 6 months (26 weeks) | 84% | 79% | 70% | 61% | 51% |
| 9 months (39 weeks) | 98% | 95% | 89% | 82% | 72% |
| 12 months (52 weeks) | 100% | 100% | 97% | 93% | 85% |
| 15 months (65 weeks) | 100% | 100% | 99% | 97% | 92% |
| 18 months (78 weeks) | 100% | 100% | 100% | 100% | 97% |
1 month ≈ 4.35 weeks. Individual puppies vary by several percentage points.
Why big dogs grow for longer
A giant-breed puppy has far more weight to put on than a toy puppy, so it keeps growing for longer, and its growth plates (the soft zones at the ends of the long bones where new bone forms) stay open longer too. That is why the giant column in the chart rises so slowly: at 6 months a giant-breed puppy has only about half of its adult weight, while a toy puppy already has more than four fifths.
Height first, then weight
Most puppies reach their adult height a few months before they reach their adult weight. After the legs stop getting longer, the chest broadens and muscle builds up. A lanky 10-month-old Labrador that looks "done" will usually still gain several pounds. Weight curves, like the one above, capture that last phase; height alone does not.
Signs your puppy is full grown
- It has reached the typical age for its size class in the table above.
- Its weight stays about the same for several weeks while it eats a normal amount.
- It no longer looks leggy or out of proportion; the chest and body have filled out.
- Your vet confirms adult proportions at a check-up.
Weigh your puppy every one to two weeks and write it down. A steady curve that flattens out is the clearest sign. Sudden gains, losses or a stall in a young puppy are worth a call to your vet.
What changes as growth ends
- Food: many puppies stay on puppy food until about 11 to 14 months, according to the AKC; small breeds can usually switch sooner, large and giant breeds later. Once growth slows, portions often need to come down. The dog food calculator shows daily calories and cups for puppies and adults.
- Exercise: the AKC advises waiting with jogging and road work until large and giant breeds are about 14 to 18 months old and their growth plates have closed. Play and normal walks are fine before that.
- Age in human years: size also changes how dogs age; see the dog age calculator.
Frequently asked questions
When do puppies stop growing?
It depends on adult size. Toy breeds are close to full grown at about 9 to 10 months, small breeds at 10 to 12 months, medium breeds at 12 to 15 months, large breeds at 15 to 18 months and giant breeds at 18 to 24 months.
At what age is a dog full grown?
Most dogs are considered adults at about one year, but large and giant breeds keep filling out for months after that. A dog is full grown when its weight stays stable for several weeks on a normal diet and it has reached the typical adult age for its size.
Do puppies stop growing in height or weight first?
Height usually comes first. Many dogs reach their adult height a few months before they finish gaining weight, as the chest broadens and muscles develop.
How much of its adult weight does a 6-month-old puppy have?
At 6 months (26 weeks) a typical puppy has about 84% of its adult weight in toy breeds, 79% in small breeds, 70% in medium breeds, 61% in large breeds and 51% in giant breeds. A large-breed puppy at 6 months can still have about 40% of its weight to gain.
When should I switch my puppy to adult food?
Many puppies stay on puppy food until about 11 to 14 months, according to the American Kennel Club. Small breeds can usually switch earlier and large and giant breeds later, once they are close to adult size. Ask your vet for your dog's breed and growth.
Sources
- Salt C, Morris PJ, German AJ, et al. Growth standard charts for monitoring bodyweight in dogs of different sizes. PLOS ONE, 2017 (basis of the simplified growth curves).
- American Kennel Club: When Does My Puppy Finish Growing? (updated June 2026): ages by size, puppy food duration and exercise advice.
This page is for general information only and does not replace a veterinarian. Puppies grow at different rates, and mixed breeds can differ from the typical curves. If you have concerns about your puppy's growth, talk to your vet. Last updated: October 2026.