We understand why it’s important for you to have an accurate estimate of your dog’s age. You want to be prepared and give your dog the appropriate care for their age, anticipate any age-related health conditions, and give them the best life possible. Knowing your dog’s age can inform many of the choices you make about their food, lifestyle, and more.

The question “How old do you think my dog is?” is complicated to answer. There are clues that veterinarians look for, including cloudy eyes, dental tartar, and how worn down the teeth are. While helpful, these methods aren’t always 100% accurate. They simply offer ways to estimate a general range of your dog’s age.

Why estimating a dog’s age is challenging

The truth is, age is difficult to determine in dogs between the ages of about 2 and 8 calendar years by physical features alone. The range is even greater for small-breed dogs, because they reach maturity faster and age more slowly than larger dogs. The aging process can be different depending on a dog’s size, genetic breed mix, and more. An adult dog is at the stage in his or her life where he or she doesn’t age visibly, quite unlike the rapid changes you see as a dog transitions from puppy to adult, or adult to senior.

If you adopted your dog fully grown, and a few years later they haven’t changed at all, it’s a good bet that your pup is in the time of life where aging is almost imperceptible: adulthood. For a medium-to-large breed dog, you can pretty comfortably say that your dog was probably about 2–4 years old at adoption; for smaller breeds, the starting range will be wider at 1–5 years old at adoption.

The good news is that in addition to physical clues, it’s now possible to use DNA to measure a dog’s age with remarkable accuracy. Keep reading to learn how veterinarians estimate dog age, and why the Embark Dog Age Test offers a new, scientific way to tell a dog’s age.

So how do veterinarians estimate dog age based on physical clues?

Body shape

A profile view of a young dog and a senior dog side by side. The senior dog shows slight muscle wasting in the hind legs.

As dogs age, the way they distribute their weight changes. Run your hands down your dog’s back on either side of the spine. With age, fat pads usually develop right over your dog’s lower back or lumbar area. Mild muscle wasting, which will lead to a more prominent spine and sometimes a sway-backed appearance, is also indicative of a senior dog. An example of slight muscle wasting is shown above.

Lens clarity

Close-up view of a young dog's eye and a senior dog's eye. The senior dog's eye shows mild cloudiness, a feature of advanced dog age.

Take a good look into your dog’s eyes. Do the pupils seem a little cloudy? This is a sign of lenticular sclerosis, an age-related phenomenon that causes the lens to become diffusely hazy or opaque, though it only minimally affects vision. 

Note that lenticular sclerosis is not the same as cataracts, which can impair vision. Cataracts are generally milky white in appearance, and can profoundly affect vision. Some breeds are more predisposed to cataracts than others, and cataracts can also develop secondary to another condition. If you suspect a cataract or are concerned about your dog’s vision, consult your veterinarian.

Coat color

Photos of a black-and-white dog as a puppy and as a mature adult shown side by side. Graying fur is visible in the senior dog's face.

Like humans, dog hair will usually begin to gray with age. Areas especially affected include the hair around the muzzle and eyes.

Note that this isn’t a particularly specific measure. Some dogs are born with a lot of white in these areas, or will gray much younger, especially wire-haired or furnished breeds. So take this with a grain of salt (and pepper!).


A puppy's teeth and an adult dog's teeth shown side by side. The puppy's teeth are sharp, clean, and white, while the senior dog's teeth show some tartar accumulation that occurs with age.

Dogs’ adult teeth are usually all in by about six months of age. Before then, your vet can age puppies by their teeth (and obvious puppyhood) with extremely high accuracy. But once the adult teeth come in, it gets tougher. Generally, dental disease, like tooth wear and loss, periodontal disease, and accumulation of dental calculus or tartar increases with age. But this is confounded by genetics: For example, small-breed dogs tend to have more severe dental disease than large dogs

Regardless of size, some dogs accumulate tartar very young whereas others are tartar-free into their senior years. It is also confounded by behavior: in a past life, did your pup chew on bones, or rocks? But depending on the dog, teeth can be a valuable piece of information (and can give your vet an idea of whether your dog might have a cleaning in the future).

Document physical changes

Another thing you can do to estimate your dog’s age is to document subtle changes over the years. Look at photos from a few years ago and compare them to photos now (and don’t forget to upload them to your dog’s Embark profile). 

Or, if you’ve just adopted your pup from the shelter, start documenting how they look right now. Take a few photos, face on, a profile of the whole body, and maybe even one from up above. Next year, and the next, take them again. Because you’re with your dog every day, the little changes in the way they look won’t be obvious to you. They are only evident when you compare them with how your dog looked a few years ago. 

Then, send the photos to your veterinarian. They want what you want—to keep your pup healthy and happy for as long as possible. The more information your vet has, the better estimate they can give you.

The most accurate way to estimate dog age

Although we’ve explored some methods veterinarians use to estimate dog age, there is now a way to know how old your dog is with much more certainty. Embark offers a Dog Age Test, which uses the science of DNA methylation to estimate your dog’s true calendar age with remarkable accuracy.

The Age Test measures the amount of methylation in your dog’s DNA, without relying on physical characteristics. This allows us to give you an accurate idea of your dog’s age, which can then help inform age-appropriate care for them throughout their life.


Dog age infographic
Embark dog age test info