Search Menu

When you bring a puppy home, you usually know their birthday and exact age. However, estimating the age of a dog rescued from a shelter can be difficult.

Why does knowing your dog’s age matter? “The reason it’s important to estimate your dog’s age is that age influences so many aspects of your dog’s quality of life: for example, diet, exercise, and healthcare requirements,” explains Dr. Jerry Klein, Chief Veterinary Officer for the AKC.

While you may not discover an actual birthdate, there are numerous observations you and your veterinarian can make that can help you estimate your dog’s age.

Physical Characteristics


Just like people, many dogs turn gray when they get older. Also, like people, this can vary greatly. However, a dog with a gray muzzle is almost always a mature adult. An older dog may also lose some hair and some elasticity or suppleness in their skin.

Bracco Italiano head portrait in profile outdoors.
©Andrea Casali-


Veterinarians will often examine a dog’s teeth to help approximate their age. By the time a dog is six months old, they should have their adult teeth. As the dog gets older, their teeth may become stained or accumulate tartar; your pet may also experience periodontal disease. The teeth will also show patterns of wearing down. If your dog’s breath is stinky, that can also be an indication of older dog teeth due to tartar buildup or disease.


Senior dogs can have cloudy or bluish eyes. This change is caused by lenticular sclerosis (also known as nuclear sclerosis), a normal change that occurs with aging in the lens of the dog’s eye. If your dog’s eyes appear white and opaque, they may also have cataracts. Half of dogs older than nine and almost all dogs older than 13 are estimated to experience one or both of these conditions.

Pads of Feet

You may have noticed that puppies have soft, pink pads on their feet. They haven’t yet put in miles of walking and running on various surfaces to condition the pads. Older dogs have hardened, darker pads that may become dry and cracked; however, this can occur in middle-aged dogs, too. Nails may also be brittle.

Muscle Tone

Healthy adult dogs are muscular, strong, and lean. Aging dogs often lose muscle tone and are more sway-backed, with a bonier look and prominent spine. Middle-aged dogs may develop fat pads over the lower back or lumbar area. Proper exercise for senior dogs can help them maintain a healthy weight, improve mobility, and minimize muscle loss.

Behavioral Characteristics

Energy Level

When you adopt an adult dog, it can take days or even weeks before they feel confident and comfortable enough in their new environment to display their true personality. However, if they maintain a continuing low level of energy and prefer to curl up and sleep away the day, it may be because they are older.

Senior Golden Retriever laying down in the grass.
©jvcron -


If a dog has trouble getting up from their nap or climbing the stairs, or they’re refusing to take long walks, they may be suffering from arthritis, which is most commonly seen in senior dogs. At least one in five dogs will develop arthritis.

If your dog seems stiff in the legs, hips, or back, ask your veterinarian for supplements that can help alleviate the pain. Consider making adjustments in your home to aid your dog’s mobility.


Another indication that your dog is no spring chicken is a poor appetite. Because old dogs are often less active and digestion is more difficult, food can become unappetizing to them. Adding warm water or chicken broth or a couple of spoonfuls of canned food on top of their kibble can make dry food more appealing. Offering unseasoned cooked chicken and rice may also help.


If your dog looks the wrong way when you call them or doesn’t bark when the doorbell rings, this may indicate a hearing impairment. Elderly dogs often suffer from degeneration in the nerves of the ear that cause hearing loss.

can dogs eat kiwi
Philary via Getty Images

Cognitive Dysfunction

A dog that displays signs of disorientation and confusion about sleep cycles and may pace and whine at night, becomes anxious, or suddenly starts doing their business in the house may be suffering from cognitive dysfunction syndrome (CDS). The prevalence of CDS is thought to be extremely high, ranging from 28 percent in 11- to 12-year-old dogs to 68 percent in 15- to 16-year-old dogs.

DNA Tests

It is possible to estimate your dog’s genetic age with a blood test. A laboratory will examine the telomere length of your dog’s DNA and compare it to those of other dogs at the same genetic level. Telomeres protect the ends of chromosomes; each time a cell divides, the telomeres become shorter until they are so short the cell dies.

Telomere length is used as a biomarker of human aging. Commercial producers of dog DNA testing kits believe that they can tell your dog’s age with a high level of accuracy.

Old Dogs, Sweet Souls

The age at which a dog is considered a senior will vary based on size and breed, and there are a variety of ways to calculate your dog’s age in human years. Veterinarians consider some dogs to be geriatric at age seven, while small dogs may not be seniors until eight or 10 years old and giant breeds may be seniors at five or six.

Welcoming a senior dog into your home can be vastly rewarding. A wise person once said, “I love puppies, but there’s nothing like the sweet soul of an old dog.”

Related article: Common Health Concerns in Senior Dogs
Get Your Free AKC eBook

Life with a Senior Dog

As your dog ages his needs will start to change. Download this e-book to learn what to expect and get helpful tips on caring for your senior dog.
*Turn off pop-up blocker to download
*Turn off pop-up blocker to download