How old is a 13 year old dog in human years
Dog Years Calculator
Quick navigation:
- Using the dog years calculator
- How do dog years work?
- Dog years to human years formula
- Dog age chart
- Limitations of the dog age calculator
- The myth of multiplying dog age by seven to get the human age
- How many dog years are in a human year?
Using the dog years calculator
This dog age calculator makes it easy to answer the question how old is my dog in human years? If you know your dog's age, just enter it as either a number of years or months. If you don't know the age, but know the dog's birth date, enter it instead and our tool will calculate the dog age in calendar years for you. Finally click "Calculate Human Years".
The output of the calculator is the number of human years, and the equivalent human age in years and months. The tool converts dog years in human years using the formula below.
How do dog years work?
The idea of 'dog years' and 'human years' is to more easily assess what stage of life your dog is: puppy, junior, adult, mature, senior, or geriatric. While different animal associations and veterinary associations might have charts and guidelines for that, for regular people it is much easier to understand when the dog's age is converted to the age of a human in an equivalent phase of physical development. For example, 9 years in dog years are equal to 66 human years, meaning that a 9-year old dog is roughly equivalent to a 66-year old person. Some use the term 'dog years' to mean 'human age equivalent years' while the scientific literature prefers the term 'human years' as more accurate.
The application of this idea is mainly in veterinary work, but it can also help dog owners appreciate the stage of life their pet is in, the physical difficulties that may entail, and so on. Both human and animal life spans have increased over time due to superior care and the availability of more economic resources which can be dedicated to animal healthcare. Continued improvements are unlikely with the current state of medical science, but should they become a reality, we would need to change the way we convert dog years to human years.
Dog years to human years formula
The dog age to human age conversion formula we use in this dog years calculator is based on research by Wang et al. (2020) [1]. Its derivation comes from the comparison of human DNA methylation changes with those of dogs. Methylation is experienced by mammalian genomes as they age and can serve as a sort of epigenetic clock. It is linked with life spans of various species and hence can serve as a model of aging.
In the equation above, HumanAge is the age equivalent of a human in years whereas DogAge is the age of the dog measured in calendar years. ln is the natural logarithm function. For example, a 12 year old dog will be nearly 71 in human years.
Dog age chart
The dog years chart below presents the equivalent human age for a given dog age. Since it was calculated using this dog years to human years calculator, it is subject to the same limitations as the tool itself.
The chart can be used to tell how old is 4 in dog years, or the reverse, e.g. what is 9 years in dog years.
Limitations of the dog age calculator
Since the research used to construct this tool was carried on 104 Labrador retrievers spanning a 16-year age range, it may have lower validity for other dog breeds. It should be used with caution for breeds that exhibit a typical lifespan much different than that of Labrador retrievers. E.g. it might work well for a Boxer, a Pitbull or a German Shepherd, but it will probably slightly overestimate the human equivalent age of a Yorkie, a Labradoodle, a Maltipoo, a Cockapoo, a Shetland sheepdog, or a Jack Russell.
Additionally, the dog years equation does not support dog age less than approximately 1.8 months. For this reason a dog age below 1.8 months is calculated as 0.3 human years, which should serve as a rough approximation.
The myth of multiplying dog age by seven to get the human age
For many years the standard advice was that in order to get the human years equivalent, one needs to simply multiply the dog age by seven. So a two year old dog would have a human age equivalent to a 14-yeard old adolescent. However, this advice was never scientifically backed. For example, most dogs would reach sexual maturity between six and twelve months old, well before the two-year mark suggested by this simple approach.
Some believe that this basic advice was given to dog owners so they would remember they need to bring in their companions for a regular check up at the veterinarian office at least one a year. If one dog year is equal to seven human years, that actually sounds like conservative advice.
How many dog years are in a human year?
Understanding the non-linear monotonic relationship between dog years and human years means asking questions like how many dog years are in a human year is meaningless. There is no single number which answers that question. To answer it, one needs to present the functional relationship across the entire life spans of both dogs and humans, just like in the dog age chart.
References
1 Wang T. et al. (2020) "Quantitative Translation of Dog-to-Human Aging by Conserved Remodeling of the DNA Methylome", Cell Systems, DOI: 10.1016/j.cels.2020.06.006
Dog Age Chart: How Old is My Dog in Human Years?
How old is your dog in human years? We used to simply multiply a dogs age by seven.However, thiscalculation isnt socut-and-dried.See our dog age calculator and chart to discover your dogsage.
Do Dogs Age 7 Years to Our 1Year?
The easy way to calculate a dogs age is to take 1 dog year and multiply it by 7 years. This is based on the assumption that dogs live to about 10 and humans live to about 70, on average. For example, a dog that is 5 years old is 35 human years.
Contrary to common belief, dogs do not age at a rate of 7 human years for each year in dog years.The number of human years piles onto a dogs life more quickly during the dogs rapid growth to maturity.
That said, this isnt a bad way to go from a health perspective because it helps us humans realize that our dogs arent the same aschildren.
As pets get older, they need extra care and attention. Small dogs are generally considered senior at seven years of age.Larger breeds are often senior when they are 5 to 6 years ofage.
Be aware of arthritis and related discomfort or irritability, weight control, sight and hearing issues, and any changes in behavior or activity that could indicate more seriousissues.
Visit your vet for exams regularly; adjustments can be made to give your pets a more comfortable, longer, healthierlife.
How to Calculate a Dogs AgeProperly
Statistics from pet insurance companies, breed club surveys, and veterinary hospitals have helped us learn more about how dogs age. According to the American Veterinary MedicalAssociation:
- The first year of a medium-sized dogs life equals approximately 15 years of a humanslife.
- The second year of a dogs life equals about nine years for ahuman.
- After that, every human year equals approximately four or five years for adog.
Dog Age Calculator: Dog Years to HumanYears
If we think like a dog, heres how a dogs age compares to a humans age! Note that this is still not a perfect calculator. There are many variations based on a dogs breed, their background, and their size.Note that this calculator is for a medium-sizedbreed of dog. Consult the chart below to see the differences between dogs of different sizes(small, medium, large, giant). Itshould give you a good sense of where your dog is in the development/agingprocess.
- Small Dog: 20 pounds orless
- Medium Dog: 21 to 50pounds
- Large Dog: 51 pounds to 100pounds
- Giant Dog: Over 100pounds
Age ofDog (dogs age according to thecalendar) | Dogs Age in HumanYears (dogs age in equivalent human years, based on average breedsize) | |||
|---|---|---|---|---|
| Small | Medium | Large | Giant | |
| 1 year | 15 | 15 | 15 | 12 |
| 2 years | 24 | 24 | 24 | 22 |
| 3 | 28 | 28 | 28 | 31 |
| 4 | 32 | 32 | 32 | 38 |
| 5 | 36 | 36 | 36 | 45 |
| 6 | 40 | 42 | 45 | 49 |
| 7 | 44 | 47 | 50 | 56 |
| 8 | 48 | 51 | 55 | 64 |
| 9 | 52 | 56 | 61 | 71 |
| 10 | 56 | 60 | 66 | 79 |
| 11 | 60 | 65 | 72 | 86 |
| 12 | 64 | 69 | 77 | 93 |
| 13 | 68 | 74 | 82 | 100 |
| 14 | 72 | 78 | 88 | 107 |
| 15 | 76 | 83 | 93 | 114 |
| 16 | 80 | 87 | 99 | 121 |
Source: AKC, How to Calculate Dog Years to Human Years
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How old is your canine companion? Tell us in the commentsbelow!
Dog age calculator: how old is my dog in human years?
Dogs experience life stages similar to humans, but they progress at different rates. For example, puppyhood lasts less than a year compared to human childhood, which lasts around 10 to 12 years before puberty. Aging is correlated to breed, as small breeds tend to develop faster and reach seniority slower than large-breed dogs.
1. Puppy
Although people still consider a dog a puppy until its around 2 years old, its only a puppy developmentally until 6 months. During their first half-year of life, your dog will grow exponentially, gaining and losing all of their baby teeth and achieving most of their height during this timespan.
2. Junior
Your dog reaches their challenging adolescent period between 6 months and a year old. Although they may still act like a puppy, theyre rapidly undergoing sexual development and will typically reach reproductive maturity between 9 months and a year.
3. Adult
After their first birthday, your dog will officially be considered an adult. At this time, you can switch them to adult food if you havent already, and theyre safely eligible to have puppies unless theyve been spayed or neutered. With most of their linear growth behind them, your dog may continue to fill out and gain weight during their second year of life, losing the gangly appearance they might have had as puppies.
The last three life stages arent as straightforward as the first three because they depend on your dogs breed.
4. Mature
A dog is mature or middle-aged when its metabolism begins to slow. At this point, make sure that they dont becomeobese. You might want to talk to your vet about switching to a low-calorie food.
5. Senior
Your dog is considered a senior during the last estimated 25% of their lifespan. For example, a dog that lives about 12 years would be a senior when it turns 9. You might consider switching to a senior diet if you havent already since dogs dont need as many calories or fat as they did in their younger years.
6. Geriatric
Not all dogs live long enough to be considered geriatric, the final period of life where age expectancy is exceeded. As they rapidly slow down, they might develop cognitive problems such asdog dementia, so youll need to account for limited mobility, making sure they dont jump down from furniture and carrying them when traveling a long distance. Still encourage them to exercise, but know their limits and dont force them.
Dog Years Converter
Use this free online dog age converter to easily convert between dog years and human years (dog age and human age equivalent). Find out how old your dog is in human years.
Quick navigation:
- Using the dog years converter
- How to convert dog years to human years?
- How to convert human years to dog years?
Using the dog years converter
This versatile converter can be used to convert dog years to human years and vice versa - human years to dog years. For example, you can use it to see how old a 10 year old dog is in human years. Alternatively, it can calculate how old is a two year old in dog years, how much is 12 years in dog years, etc.
To use the tool, simply choose the input metric - dog years or months, or human years or months, and the desired output metric. Then enter the age of either the dog (if entering dog years/months) or the person (if entering human years/months). Obviously, if for some reason you know the human age of the dog but not its calendar age, then you can certainly enter that as input.
How to convert dog years to human years?
In order to do the conversion our tool uses a recently developed equation based on DNA methylation analyses performed on a set of Labrador retrievers as described by Wang et al.[1]. The equation arrived at by this recent (2020) research is why our tool can provide a much better estimation compared to the usual advice given for this problem which is to simply multiply the number of calendar years by seven in order to get the human equivalent age of the dog. The formula itself is:
Human Age = 16 ln(Dog Age) + 31
Both ages above are in years, and ln() denotes the natural logarithm function. For example, 8 years in dog years would be calculated as: 16 ln(8) + 31 = 16 2.08 + 31 = 33.28 + 31 = 64.28 years or roughly 64 years in human age equivalent (logarithm of 8 is 2.08).
For your convenience, we have also tabulated some key values in the conversion table below. It can obviously be used both ways.
| Dog Age | Human Age |
|---|---|
| 3 months | 8.8 years |
| 6 months | 19.9 years |
| 9 months | 26.4 years |
| 1 year | 31.0 years |
| 2 years | 42.1 years |
| 3 years | 48.6 years |
| 4 years | 53.2 years |
| 5 years | 56.8 years |
| 6 years | 59.7 years |
| 7 years | 62.1 years |
| 8 years | 64.3 years |
| 9 years | 66.2 years |
| 10 years | 67.8 years |
| 11 years | 69.4 years |
| 12 years | 70.8 years |
| 13 years | 72.0 years |
| 14 years | 73.2 years |
| 15 years | 74.3 years |
| 16 years | 75.4 years |
| 17 years | 76.3 years |
How to convert human years to dog years?
The conversion from human years to dog years happens by using the same formula as above, but in reverse. Our tool uses iterative approximation with a step of 0.1 years to pinpoint the dog age which corresponds to the human age you enter. It is something you can attempt to do by doing the math by hand, but it is not advisable. The dog age conversion tool above will do this with no effort.
Using a dog age chart can also be used if approximate results are admissible.
References
1 Wang T. et al. (2020) "Quantitative Translation of Dog-to-Human Aging by Conserved Remodeling of the DNA Methylome", Cell Systems, DOI: 10.1016/j.cels.2020.06.006
