How old would my dog be if he were a human?

To get it straight, to convert dog years exactly into a human age is not easy. The old formula that one dog year equals seven human years is completely outdated. But there are some other interesting approaches to making comparisons, and we’ll introduce them to you now.

Convert dog years to human years: is it possible?

You can make comparisons using certain tables and formulas, yet there are some other differences in age between dogs and humans that you need to consider:

• Dogs mature and age fundamentally differently than humans.
• A dog probably has a very different sense of time than a human.
• Dogs do not care about their age.

How and whether dogs perceive time and whether they are in any way interested in the aging process is not known. This is probably not the case with our pets – we, on the other hand, have made a big deal out of age and aging.

Given that, maybe you just want to know from when your dog is old and if you have to pay attention to something. More on this later.

The x 7 rule

In the past, the rule of thumb was that one dog year was roughly equivalent to seven human years. Consequently, the dog ages in one calendar year as fast as a human being ages in seven years.

This formula is outdated today. The fact alone that a Yorkshire Terrier can live up to 20 years and a Great Dane only seven or eight years shows that this comparison is flawed.

Even with all the other formulas, you must always remember that they can only be approximations.

Dogs age very differently than humans

People who have reached an advanced age often experience significant limitations in their musculoskeletal system, they become forgetful and tooth loss sets in. They often suffer from organic disorders, cardiac dysfunction or other degenerative diseases.
For many of us, vision begins to deteriorate at the age of 40, our hair turns completely gray, our skin becomes wrinkled, and our sensory abilities diminish.

If you look at old dogs on average, most of them are still much more agile than a very old human, even in old age. They walk, run, wag, jump around – all perhaps a little slower than when they were younger, yet the activity level in senior dogs is higher than in humans. They also very rarely turn completely gray.

Many dogs know osteoarthritis in old age, but even then they are still active. Even when dogs have serious illnesses, they often do relatively well until almost the end. The senses are usually excellent even in old age and dogs don’t completely lose their teeth.

This does not mean that there is not dementia and diseases in old dogs. They just deal with it differently than we humans do. The likelihood that your four-legged friend will stay fit and agile much longer than a “same age” human is high.

Nevertheless, we now dare to make the big comparison and get a little closer to the question, “How old is my dog in human years?”.

How can I convert my dog’s age into human years?

Meanwhile, there is a new calculation formula, which includes the differences between the size and average weight of the dog breed.

Accordingly, a 6-month-old dog is

• In the weight class up to 15 kg (final weight): 15 years old
• 15 to 45 kg: 10 years old
• over 45 kg: 8 years old

Accordingly, an 8-year-old dog is

• up to 15 kg: 52 years old
• 15 to 45 kg: 63 years old
• over 45 kg: 76 years old

Accordingly, a 12-year-old dog would be

• up to 15 kg: 68 years old
• 15 to 45 kg: 85 years old
• over 45 kg: over 100 years old

Life expectancy of different dog breeds

A dog over 45 kilograms would have reached 100-year-old status by the time it was 11 years old.

Why do smaller dogs live longer than larger dogs?

Now you probably noticed that the little ones were much older than the big ones in the beginning. Overall, however, they are getting older than the big ones. This is due to the fact that the small breeds mature faster, but then age much slower than Great Danes, St. Bernards and Co. The large breeds, on the other hand, are overall late developers and then age faster.

American scientists finally want to find out why small dogs live longer than larger dogs.
They observed the animals during the growth phase in puppyhood. They found more metabolic residues, so-called free radicals, in the bodies of the large and faster-growing breeds. These indicate oxidative cell stress, which, by the way, can also accelerate the aging process in us humans.

In the large breeds, only the proportional body growth is larger and faster. As you have already read in a previous paragraph, the large dogs are comparatively “younger” than the small breeds. Here you have to distinguish between pure mass growth and maturation in general.

Calculate dog age: What is the correct formula now?

Another related formula was established by the American Veterinary Medical Association (AVMA):

• The first year of a medium-sized dog’s life is equivalent to 15 years of a human’s life.
• The second year of life of a medium-sized dog corresponds to about nine years.
• After that, each human year multiplied by 5 counts.

There is no formula that allows to convert dog years into human years with one hundred percent certainty. The question of how “old” your dog really is, you must answer by observation in addition to calculations.

How do I know how old my dog is?

As with us humans, there are dogs that age faster than others due to obesity, degeneration, adverse living conditions or other factors.

Look at your dog and consider if he looks old to you.

• Does he have limitations in walking?
• Do white hairs show on the muzzle?
• Is he slowing down or getting more comfortable overall?

What do I do when my dog is old?

You may have concerns about your dog’s age or even fear of losing him. In these cases, only two things help:

1. Take care of preventive examinations in time. As a rule of thumb, small as well as larger dogs reach senior age after 8 years of age. In very large or extremely overbred and therefore less long-lived dogs, it may be earlier. Talk to your veterinarian about when he or she recommends regular checkups. If you go for a check-up once a year and keep a close eye on your dog, you will most likely notice any signs of old age or serious illness.
2. Otherwise, you should always take good care of your dog, provide him with optimal food as well as give him a species-appropriate life and a lot of joy at your side and let the age be secondary.

How else can you tell how old a dog is?

Veterinarians can estimate a dog’s age from this, among other things:

• Condition of the teeth.
• Condition of the coat and coloring.
• Blood work and x-rays if necessary.

If you take on an older dog or the age is not known for some other reason, you will get a rough to excellent estimate this way.

Dog years in human years – Conclusion

Tables and formulas that convert dog years to human years can only provide approximations. The differences between breeds, large and small dogs and the general aging process are too great to make any binding statements.

Nevertheless, the formulas provide you with an approximate value. Pay special attention to the entry into the senior age from 8 years and prepare for regular check-up examinations at the veterinarian.