How to Calculate Dog Years in Human Years?

How to calculate dog years in human years

Dog Age Chart: How to Calculate Dog Years in Human Years?

For several years now, it has been believed that a dog’s age is calculated by multiplying their age by seven; i.e., every one of their years is equal to seven human years. That theory has been replaced with a more scientific formula with greater accuracy. This formula is based on the methyl groups in dogs and the changing patterns of these methyl groups when studied along with the human genomes. The formula is a more effective way of understanding your dog’s age because no two species age at the same rate. This formula is an epigenetic clock that helps in understanding the age of cells and tissue in your dog.

Why is understanding a dog’s age important?

It is important to understand the age of your dog because it helps in preparing for anti-ageing interventions. You can anticipate age-related problems in your dog and prepare for it well in advance. With a more precise calculator, there are greater chances of accurately evaluating the age and related physical conditions. Dogs, as they age, will need different levels of care, including their nutritional needs, the frequency of health check-ups, the level of exercise, and the additional supplements needed to maintain good health. Knowing their age and what can be expected at each year will ensure that you are proactive in taking care of problems that may arise. 

How to Calculate Dog Years?

The size and breed of your dog need to be kept in mind when calculating age. The tiny dogs do not come under the ‘older dogs’ category even though they may be ten years old. Large-sized dogs, on the other hand, will be considered middle-aged when they are around five years old. There are different ways of arriving at the age of the dog. One of them is by checking their teeth. However, this varies depending on the breed. It also varies because of the level of dental care the dog has received. Dogs have all their baby teeth by the time they are eight weeks old. By seven months, they have their permanent teeth in. As they grow older and between ages 1 one and two, their teeth start becoming yellow and dull. Around three years and after, tartar builds up and you can see some wear on their teeth. This continues over the next few years showing more signs of wear and even a little disease creeping in. When they are ten years old and older, the teeth are quite worn, and some teeth may even be missing. 

Apart from looking at the teeth for age, a physical exam may be undertaken, and a look at the joints and bones will be able to get you closer to the real age of your dog. Other signs include greying around the muzzle, loose skin, stiffening of the joints, reduced energy, some changes in behaviour such as anxiety, and hearing problems. 

Dog Age Chart

Dog’s AgeAge in Human Years
Breed TypeSmallMediumLargeGiant
1151515 12

Clues to look for while guessing a dog’s age

Sometimes when you adopt a puppy or dog, you might not know their history or exact age. Even if you don’t know the birth date, you can still guess their age by analyzing their teeth. 

  1. By 8 weeks, all baby teeth are in and growing.
  2. By 7 months, all permanent teeth are in and are white and clean.
  3. By 1-2 years, teeth are duller and the back teeth may have some yellowing.
  4. By 3-5 years, all teeth might have tartar build up and some tooth wear. 
  5. By 5-10 years, teeth show more wear and signs of disease.
  6. By 10-15 years, teeth are worn and heavy tartar build up is likely. Some teeth may be missing. 

Some more signs of aging in dogs:

  1. Cloudy eyes
  2. Grey hair which starts around the muzzle and then spreads to other areas of the face, head, and body. 
  3. Loose skin
  4. Stiff legs
  5. Trouble hearing or seeing
  6. Stiff muscles and joints, arthritis
  7. Lower activity level
  8. Behavioural changes such as increased anxiety
  9. Confusion, accidents in the house, irritability, etc.

Why do smaller dogs live longer than larger dogs?

Do smaller dogs live longer? There has not been scientific proof that this is true. But, in general, large mammals such as elephants live longer. Among dogs, it has been found that larger dogs age faster at an accelerated pace. This pace is believed to the possibility of cell growth abnormalities. It has also been found that larger dogs succumb to diseases that are age-related much sooner. Research shows that for every 4.4 lbs of body mass, life expectancy is reduced by a month. 

Bottom line

Relying on recent research, it is clear that dogs do not age at the rate of seven human years for every dog year. The current study shows that:

  • In a medium-sized dog, the first year of life is equivalent to 15 years of a human’s life.
  • In their second year, their age is equivalent to around nine human years. 
  • Beyond the second year of your dog’s life, each human year is equal to about four or five years for a dog.

Know of an older dog that needs help? Contact VOSD

Do you know a stray dog that has no other home and struggling to survive on the streets due to old age related issues? Have you tried looking everywhere but no luck? VOSD takes in dogs that have no hope of finding a home, no matter what age. If you know of a dog that needs a home, reach out to VOSD. We provide premium medical care and comfort to any dog that joins the VOSD family through our surrender process. Note we have 10 surrender categories out of which 6 are free. For more information, check out:

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