Growth timeline by size
| Adult size | Example breeds | Height done | Fully filled out |
|---|---|---|---|
| Toy (under 12 lb) | Chihuahua, Yorkie, Maltese | 8 to 10 months | 10 to 12 months |
| Small (12 to 25 lb) | Shih Tzu, Frenchie, Cavapoo | 9 to 11 months | 12 months |
| Medium (25 to 50 lb) | Border Collie, Husky, Corgi | 10 to 12 months | 12 to 15 months |
| Large (50 to 100 lb) | Lab, Golden, German Shepherd | 12 to 15 months | 18 months to 2 years |
| Giant (over 100 lb) | Great Dane, Mastiff, Newfoundland | 15 to 18 months | 2 to 3 years |
Signs your puppy is nearly done
- Weight gain slows to a trickle over several weeks
- Paws look in proportion rather than oversized
- Growth plates are closed on X-ray. This is the only definite answer, and your vet can check it.
Why it matters
Growth plates are soft until they close. Heavy, repetitive impact exercise (long runs on pavement, lots of jumping) is best limited until then, especially for big breeds. Switch to adult food once growth is mostly done, and keep your dog lean. Excess weight while growing raises the risk of joint problems.
Estimate your puppy's adult weight with the puppy weight calculator.
Frequently asked questions
Do puppies have growth spurts?
Yes. Most growth happens before 6 months, often in bursts. Puppies may eat and sleep more for a week or two during a spurt.
Does neutering affect growth?
Neutering before growth plates close can make dogs slightly taller, and in some large breeds early neutering is linked to higher joint risk. Discuss timing with your vet.