We understand why it’s important for you to know how old your dog is. You want to be prepared and give them the appropriate care for their life stage, 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 is it challenging to estimate a dog’s age?

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 their life where they don’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.

Using DNA to estimate a dog’s age

Curious about your dog’s age? The Embark Age Test uses the science of DNA methylation to estimate a dog’s age and birthday.

Dog Age Test
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Studying the relationship between methylation and age is a cutting-edge area of science. As dogs age, the level of DNA methylation changes in a predictable way. We use the amount and position of DNA methylation as a type of “clock” to estimate how old your dog is.

How veterinarians estimate dog age

So how do veterinarians estimate dog age? There are four main ways to tell how old a dog is using physical clues.

1. How to tell a dog’s age using 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. 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. To tell how old your dog is using their body shape, run your hands down your dog’s back on either side of the spine and see if you notice any of these indicators of age. 

2. How to tell a dog’s age by their eyes

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.

Cloudy pupils are another indicator of a dog’s age. They are 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. Take a good look into your dog’s eyes. Do the pupils seem a little cloudy?

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.

3. How to tell a dog’s age using 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.

The development of gray in their coat is a third way to estimate how old a dog is. Like humans, dog hair will usually begin to gray with age. Areas especially affected include the hair around the muzzle and eyes.

Note that coat color isn’t a particularly specific measure. Some dogs are born with a lot of white in these areas, or will gray much younger than others, especially wire-haired or furnished breeds. 

4. How to tell a dog’s age using their teeth

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.

When a dog is young, a veterinarian can age puppies using their teeth (and obvious puppyhood) with extremely high accuracy. Estimating a dog’s age becomes more challenging once all their adult teeth are in, usually by six months of age. Generally, the accumulation of dental calculus and tartar, tooth wear and loss, and periodontal disease increase with age. However, this is not always the case, and it can be 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 need a cleaning in the future).

Documenting physical changes can help you estimate a dog’s age

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 dog healthy and happy for as long as possible. The more information your vet has, the better estimate they can give you.



Dog age infographic