How Old Is My Dog in Human Years?
Many people say one dog year is the same as seven human years. This is an easy rule, but it is not very true. Dogs grow up much faster than people in the first two years, and then they age more slowly. Big dogs also age faster than small dogs.
This dog age calculator uses your dog's birth date and size to give you a better guess of the age in human years.
How the Dog Age Calculator Works
The tool uses a simple, well known way to count:
- The first year of a dog's life is about 15 human years.
- The second year adds about 9 more, so a 2 year old dog is about 24.
- After that, each dog year adds about 4 human years for a small dog, 5 for a medium dog, 6 for a large dog, and 7 for a giant dog.
This is a guide and not an exact science. Other charts use different ways to count, so their numbers may be a little different from ours.
Dog Age Chart by Size
Here is the age in human years for each size group:
| Dog age | Small | Medium | Large | Giant |
|---|---|---|---|---|
| 1 year | 15 | 15 | 15 | 15 |
| 2 years | 24 | 24 | 24 | 24 |
| 3 years | 28 | 29 | 30 | 31 |
| 5 years | 36 | 39 | 42 | 45 |
| 7 years | 44 | 49 | 54 | 59 |
| 10 years | 56 | 64 | 72 | 80 |
| 12 years | 64 | 74 | 84 | 94 |
| 15 years | 76 | 89 | 102 | 115 |
Dog Life Stages
Puppy
Your dog is a puppy for the first year, or a little longer for big breeds. This is a time for shots, training and fast growth. Our puppy feeding calculator can help you plan the meals.
Young adult
Between 1 and about 2 and a half years, your dog is full of energy and still learning. Many dogs reach their full weight in this time.
Adult
This is the longest stage. Food, exercise and a yearly vet check keep your dog in good shape.
Senior
Small dogs are usually seniors at about 10 years, medium dogs at 9, large dogs at 8, and giant dogs at around 6. Senior dogs move less and may need less food, so check the amount with our dog calorie calculator.
Why Do Big Dogs Age Faster?
Vets do not fully know why, but big dogs seem to grow so fast that their bodies wear out sooner. A giant dog may live around 8 years, while a small dog may live 14 years or more. These are only averages, and many dogs live longer.
Caring for Your Dog at Every Age
- Puppies need vet visits every few weeks at first for shots and checks.
- Adult dogs should see the vet about once a year.
- Senior dogs do best with a check about every 6 months.
- At any age, a healthy weight helps your dog live longer. Try our healthy dog weight calculator to see if your dog is in a good range.
This tool is a general guide and not vet advice. If your dog seems slow, tired or in pain, please talk to your vet.