Dog age Calculator

Choose and add the values to know how old is your dog in human years.



Created by Helen Stark
Helen Stark
Helen Stark

Student of Harvard university, she loves to observe new things about society, she studies Wikipedia more and learns about quantum physics on the internet. She loves dancing and singing songs.

Full Bio

Reviewed by Nick Walker
Nick Walker
Nick Walker

Done PHD of nuclear physics from the University of Pennsylvania. He is always seeking ways to explain science in easy terms. Moreover, he loves coffee & its beans more than his girlfriend (not at all).

Full Bio

This dog age calculator is used to find your dog's age in human years. It helps to make calculations for a dog's size, age, breed, and equivalent human life expectancy. Use our calculator to get your dog's age-related milestones and equivalent human age for a better understanding of their health and behavior.

Dog Years Vs Human Years:

Everyone knows how age is measured in years, but measuring a dog’s age is different as compared to human years. The American Veterinary Medical Association has established general guidelines to determine your dog's age in human years:

When dogs are young, they age more rapidly than humans in terms of physical development and maturity. For instance, the human age of a medium-sized one-year-old dog is 15 human years.

As dogs get older, the rate of aging slows down. The second year is equal to 9 human years and after that each year is considered approximately 4 or 5 years.

Larger dogs tend to age more quickly in their early years but when they reach their senior years, then they might age more slowly compared to smaller breeds. Factors like breed, size, genetics, and overall health also influence the aging process.

Comparing dog years to human years is a way to understand a dog's age and helps to understand their growth and development.

Do Dogs Really Age Seven Times Faster Than Human?

The general rule that one dog year is equivalent to 7 human years is a common misconception. However, it does not hold accuracy in terms of the aging process in dogs.  

Although there's no doubt that dogs age at a faster rate as compared to humans during their beginning years, the aging rate becomes slow as they get older.

However, still, there's not really an exact formula that reveals how dogs age in comparison to humans. No matter whether your dog is small or big, our dog age calculator shows how your dog is older/younger than you.

How Do I Calculate My Dog’s Age in Human Years?

Calculating your dog's age in human years including several formulas that are typically based on the dog's size and breed. These are some general equations that helps to make calculations: (Changed)

For Small to Medium-Sized Dogs:

  • 1st year is equivalent to 15 human years
  • 2nd year will be equal to 9 years
  • After that, every additional year is about 4 years


Human_Years= 15(For First Year) +9(For Second Year) + (4 * Additional Dog Years)

For Large to Giant-Sized Dogs:

  • 1st year is equivalent to 12 human years
  • 2nd year is equal to 7 human years
  • Each additional year is equal to 5 human years


Human_Years= 12(For First Year) +7(For Second Year) + (5 * Additional Dog Years)

Apart from that, you can check your dog’s age quickly with our dog age calculator. Just select its breed and enter age to know how old it is when converted to human years.

How Long Do Dogs Usually Live by Size?

The life longevity of dogs is dependent on their adult size and breed, such as:

  • Smaller breeds live for up to 10-15 years
  • Medium breeds have a life of 10-13 years
  • Giant dogs have the smallest lifespan compared to all

The table below provides a clear overview of typical dog lifespans based on their sizes:

Size Average Lifespan
Small 12 - 16 years
Medium 10 - 14 years
Large 8 - 12 years
Giant 6 - 10 years

Dog Age Chart:

Dog Size








Dog Age Equivalent Human Years
1 15 15 15 15
2 24 24 24 24
3 28 28 28 28
4 32 32 32 32
5 36 36 36 36
6 40 42 45 49
7 44 47 50 56
8 48 51 55 64
9 52 56 61 71
10 56 60 66 78
11 60 65 72 86
12 64 69 77 93
13 68 74 82 101
14 72 78 88 108
15 76 83 93 115
16 80 87 99 122


Why Is Understanding My Dog’s Age Important?

The actual reason behind dog age calculation is to check whether they are aging properly or not. This helps to take better care of the pet according to their life stage.

What are Common Signs of Aging In Dogs?

As our dogs grow older, they exhibit certain signs that indicate the natural aging process. Let's explore the common signals that let us know our furry friends are getting a bit older.

  • Gray Hair
  • Reduced Energy
  • Slower Movement
  • Joint Stiffness
  • Poor Eyesight
  • Changes in Sleep Patterns
  • Reduced Hearing or Vision
  • Dental Issues
  • Changes in Appetite
  • Weight Gain or Loss
  • Behavioral Changes

What To Expect When Your Dog Turns 13?

When your dog turns 13, you may see some changes in your dog including:

  • Cloudy Eyes
  • Weight Gain
  • Swelling
  • Extra Anxiety

At this age, it is common for the dog to spend most of the time sleeping and respond slowly. If your dog sleeps too much, it’s due to some sort of medical disease that must be treated timely.

Related: Similar to dog owners, cat owners may want to know the age of their cats in human years. They can try our Cat age calculator. As it is designed to provide a precise estimation of a cat's age in human years.