What Age Is a Dog Fully Grown?

Growth and Maturity of Dogs

• Dogs reach full growth between 1 and 2 years old.
  • This depends on breed and size. Most dogs stop growing in height around 9-12 months, with larger breeds possibly continuing until 18-24 months.
• Estimating Adult Weight of Puppies
  • To calculate adult weight, divide the puppy’s weight at 20 weeks by 20 then multiply by 52. Or double the 6-month weight. Paws do not determine ultimate size.

Factors Affecting Growth

• Small, Medium, and Large Breeds
  • Small breeds typically stop growing at 6 to 8 months old. Medium breeds stop around 12 months, while large breeds finish growing around 14 months old. Some large breeds fill out until 24 months old.
  • Genetics, nutrition, exercise, health, and spaying/neutering status affect growth rate.

Understanding Maturity

• 16 Weeks to Adult Size
  • Around 16 weeks old, most puppies are half-grown depending on the estimated maturity rate by breed. At 6 months, medium-to-large breed puppies weigh about two-thirds their adult weight, and giant breeds are about half their adult weight. Pay attention to diet to avoid growing too fast.