Dog Life Stages: From Puppy to Senior

Life stages at a glance

The calculator and breed pages use five life stages: puppy, adolescent, adult, mature and senior. The table shows roughly when each stage begins for the different sizes, and what that equals in human years.

Puppy (under 1 year)

Puppyhood is a time of rapid growth and a great deal of learning. The first months are crucial for socialisation, and puppies need food formulated for growth. Large breeds should grow at a controlled pace to protect their joints.

Adolescent (1–2 years)

The dog is sexually mature but still developing, both physically and mentally. Many dogs test boundaries during this period, and patient training pays off. Large and giant breeds may still be growing.

Adult and mature

As an adult, your dog is fully developed and often at its best. The focus is on keeping a healthy weight, caring for its teeth and making sure it gets enough activity.

The mature stage begins a couple of years before senior age. The first signs of ageing may appear, and it's a good time to talk to your veterinarian about preventive care.

Senior

Senior dogs often need more rest, adjusted exercise and closer follow-up. Many older dogs appreciate soft bedding, warmth and predictable routines. Read more in the guide on when a dog is considered a senior.