How Old Is My Dog? Tips On How To Tell A Dog’s Age


Last Updated: August 28, 2023 | 5 min read | Leave a Comment

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old dog laying on the ground with a birthday hat on and a cupcake with candle

If you get a puppy from a breeder or adopt a dog from a long-term owner, it’s usually easy to know how old your dog is. But rescuing an adult dog or even an older puppy can present challenges in determining your new furry friend’s age. Why does it matter to know your dog’s age?

It’s important to estimate your dog’s age for dietary, exercise, and regular healthcare needs. If you’re wondering, “How can I tell how old my rescue dog is?” we have several tips on how you (and your veterinarian) can estimate your pup’s age to give her the appropriate care she needs.

Can A Vet Tell How Old A Dog Is?

Soon after you adopt a new furry family member, it’s important to get her examined by a veterinarian. Part of your vet’s initial checkup will include assessing your pup’s current medical condition and age range. While a vet is better equipped to estimate how old a dog is, that doesn’t mean it’s an easy feat.

“I’m asked to estimate a dog’s age quite regularly, usually when seeing a newly adopted rescue dog for the first time,” says Dr. Hannah Godfrey, BVetMed, MRCVS, a small animal veterinarian in Cardiff, Wales. “When assessing a dog’s age, I first look at their general external appearance – is their fur looking a little gray around the muzzle? Are they carrying extra weight or looking a little skinny? Are they standing as if their joints are stiff or sore? Do they have any other potential age-related signs like cloudiness of the eyes (corneal edema) or warty lumps?”

“All of these signs may suggest an older age, but can also be present in younger dogs, so I wouldn’t make an estimate based on these facts alone,” explains Dr. Godfrey. “By assessing their teeth, size, and body shape, as well as looking at how they behave, I can determine whether they are an older pup or a young adult dog.”

How To Tell How Old A Dog Is

While it’s nearly impossible to determine your rescue dog’s exact age, there are several ways you can narrow down a general age range. Still, it can be quite difficult to tell how old a dog is between the ages of two and seven years old. To further complicate things, the aging process is different depending on a dog’s size, breed mix, and other factors.

Examine Your Dog’s Teeth

Checking out the condition of your furry friend’s teeth may shed some insight into her age range. How can you tell the age of a dog by teeth? Dr. Godfrey explains, “If I notice the dog has baby teeth, they’re likely to be less than 6 months old, but this is usually quite obvious from their general appearance and demeanor! If I look at their teeth and they are adult teeth but look very clean and white, that would suggest that they are aged between six months and two years.”

Dr. Godfrey adds, “Once a dog is older than around two years, it’s not so easy to be sure of their age based on their teeth, because it will depend on whether their previous owners took care of their teeth or not. However, in general, a dog with mild tartar build-up would be more likely to be middle-aged, while a dog with severe dental disease, or even missing teeth, is more likely to be over the age of eight to 10 years.”

lily dog standing in the grass
Michelle’s dog Lily (Photo Credit: Alison Shermeta)

“When we adopted Lily from our local Forsyth Humane Society, they told us she was five years old. But when we took her to our vet for her first checkup, they said her teeth suggested she was four. So who knows, but we are going with the younger age, especially now that it puts her at 14.5 rather than 15.5 years of age!”

Michelle Schenker, Canine Journal co-founder and mixed-breed rescue parent

Check Out Her Coat

Many dogs gradually turn gray as they age, just like their owners. And similar to people, the beginning of the graying process can vary widely. The most prominent graying usually appears on their muzzle, but it can also occur anywhere on their body. In general, dogs develop some white or gray fur on their muzzle between seven and 10 years of age. But some breeds, like Golden Retrievers, can start to gray at four or five years old.

Other dogs can prematurely gray due to temperament or behavior issues. In a 2016 study of 400 dogs ranging in age from one to four years old, scientists found that high anxiety or impulsive behaviors are strong predictors of premature graying in dogs.

Gaze Into Her Eyes

Another predictor of a dog’s age is cloudy, bluish-gray pupils, a sign of lenticular sclerosis. This condition is a normal part of aging in dogs and typically develops between six and eight years old. Lenticular sclerosis doesn’t majorly affect a dog’s vision, but cloudy eyes can also be a sign of cataracts, a serious condition that can lead to blindness.

Consider Muscle Tone & Body Condition

Healthy young adult dogs are lean and muscular. As they reach middle age, some dogs develop fat pads over their lower back or lumbar region. Weight gain is also a concern for older adult dogs. Dogs often lose muscle tone as they move into their senior years, which can lead to a more prominent spine or a sway-backed appearance.

4 Behavioral Factors

Other ways to estimate your dog’s age range include observing your pup’s mobility and behavior. However, the following indicators are only helpful in determining whether your pup is moving from middle age into her senior years.

  • Energy level: This indicator can vary greatly by breed, but younger adult dogs typically are very active, energetic, and always happy to play. Older adult dogs tend to gradually slow down as they age and sleep more during the day.
  • Mobility: Healthy young adult canines are agile with no problems moving around. Older dogs may start to show signs of stiffening joints or arthritis and have trouble climbing stairs, taking long walks, etc. Joint supplements can help improve mobility and reduce joint pain in aging dogs.
  • Hearing: Senior dogs often show signs of hearing loss. You may notice that your pup doesn’t come when you call or no longer barks when the doorbell rings.
  • Appetite: As dogs enter their golden years, their appetite may decrease due to a lower activity level, problems digesting food, or a lack of interest in their current food. You may want to consider changing your pup’s diet if this occurs. See our reviews of the best dog food for picky eaters for some tasty, healthy options.

Consider DNA Testing

An at-home DNA test kit may be helpful to narrow down your pup’s biological age, giving you a better idea of nutritional, exercise, and healthcare needs. These tests require a simple cheek swab, which you mail back to the company’s laboratory. You get results within a few weeks, which you can then share with your vet.

EasyDNA Canine Genetic Age Test

EasyDNA dog test

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The Canine Genetic Age Test offered by EasyDNA measures the length of your dog’s telomeres as a biomarker of biological ageTelomeres are protective caps at the end of each chromosome that progressively shorten with age.

Once the lab receives your dog’s DNA sample, scientists measure the telomere length and compare it with thousands of similar dogs in their database to determine your dog’s biological age. Biological age is different than chronological or actual age since it provides insight into the predicted longevity and health of the tested canine.


  • Canine Genetic Age Test: $79

EpiPaws Pet Age Test Kit

EpiPaws Pet Age Test Kit

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EpiPaws pet age test kit takes a different scientific approach (based on previous research) than EasyDNA’s test to determine how old your dog is. EpiPaws’ method involves the analysis of your dog’s DNA methylation, which changes over time in a fairly steady manner as dogs (and humans) age.

DNA gets chemically modified over our lifetime, and one of these modifications involves the addition of methyl groups that stick to specific DNA sequences over time. And some scientists believe analyzing this DNA methylation is an accurate predictor of biological age.


Don’t know what breeds make up your adopted pup? See our reviews of the best dog DNA tests, including breed identification tests and genetic mutation testing, to uncover any possible inherited health conditions and more.

How Old Is My Dog In Human Years?

Did you know that the long-held belief that one dog year equals seven years for a human isn’t based on any scientific evidence? In fact, it’s not a reliable method at all. See our article on how to calculate dog years to human years to see the current formula to use if you’re curious about how old your dog is compared to you.

The information provided through this website should not be used to diagnose or treat a health problem or disease; it is not intended to offer any legal opinion or advice or a substitute for professional safety advice or professional care. Please consult your health care provider, attorney, or product manual for professional advice. Products and services reviewed are provided by third parties; we are not responsible in any way for them, nor do we guarantee their functionality, utility, safety, or reliability. Our content is for educational purposes only.

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