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Pet Age Calculator

Dog and cat age in human years from the AVMA chart: 15 at year 1, 24 at year 2, then 4 a year for a cat and 4 to 6 for a medium dog, up to 16. How it works

Use the Pet Age Calculator

Pet type

The AVMA dog column is based on a medium-sized dog weighing 21 to 50 lbs. Weight and breed change how a dog ages.

Human age equivalent
36 years old

A 5 year old medium-sized dog is roughly 36 in human years by the AVMA table.

How it works

The old rule of "multiply by 7" does not fit pets. This tool reads the American Veterinary Medical Association (AVMA) table: year 1 is 15 human years and year 2 is 24 for both dogs and cats. After that a cat adds 4 a year, and a medium-sized dog adds about 4 to 6 a year (the table is not a straight line).

The AVMA says pet ages are approximate calculations and to ask your veterinarian for your pet's age in human years. The table stops at 16 years, so there is no figure above that.

Actual age and human years (AVMA)
Actual age (years)CatMedium-sized dog
11515
22424
32828
43232
53636
64042
74447
84851
95256
105660
116065
126469
136874
147278
157683
168087

About the Pet Age Calculator

A 5-year-old dog or cat is 36 in human years on the American Veterinary Medical Association chart. Both start at 15 for year 1 and 24 for year 2; after that a cat adds 4 a year and a medium-sized dog of 21 to 50 lb adds 4 to 6. This pet age calculator reads the chart for ages up to 16 years and works out the months in between.

Dog and cat age in human years (AVMA chart)

Actual ageCatMedium-sized dog (21 to 50 lb)
1 year1515
2 years2424
3 years2828
4 years3232
5 years3636
6 years4042
7 years4447
8 years4851
9 years5256
10 years5660
11 years6065
12 years6469
13 years6874
14 years7278
15 years7683
16 years8087

The AVMA calls these approximate calculations and suggests asking your veterinarian for your pet’s age in human years. Its dog column is based on a medium-sized dog of 21 to 50 lb, and it notes that weight and breed, among other factors, may influence aging.

Methodology

The page looks up the AVMA chart for whole years from 1 to 16. Between two whole years it draws a straight line, and under 1 year it draws a straight line from 0 to 15. The result is rounded to a whole year. The in-between figures are the page’s arithmetic, not AVMA numbers. Years and months accept decimals; months must be under 12 and the total age 16 years or less. With I know the birth date, the age is the whole calendar months from the birth month to the current month on your device, so the day of birth is ignored.

Frequently asked questions

How old is a 7-year-old dog in human years?
A 7-year-old medium-sized dog is 47 on the AVMA chart, and a 7-year-old cat is 44. A dog of 7 years 6 months comes to 49.
Is one dog year equal to seven human years?
Not on the AVMA chart. A 1-year-old dog is 15, not 7, and a 10-year-old medium-sized dog is 60, not 70. The chart climbs fast in the first two years and more slowly after that.
How do you convert cat years to human years?
Count 15 for the first year, 24 at two, then add 4 for each year after: a 10-year-old cat is 56 and a 16-year-old cat is 80.
How old is a 6-month-old puppy or kitten in human years?
The AVMA chart starts at 1 year, so the page draws a straight line from 0 to 15 across the first year. 6 months gives 7.5, shown as 8. That figure is the page’s arithmetic, not an AVMA number.
Does a dog’s size change its age in human years?
The AVMA dog column is for a medium-sized dog of 21 to 50 lb, and the AVMA notes that weight and breed may influence aging, but the chart gives no other column. The page has no size setting. Older links that include a size open with a note that the figure is for a medium dog.
Can I enter my pet’s birth date instead of its age?
Yes. Choose I know the birth date and pick the birth month and year. The page counts whole calendar months to the current month on your device: a dog born in April 2021 is 5 years 6 months old in October 2026, which is 39 in human years (a cat, 38). The day of the month is not asked, so the age can be up to a month ahead. A link can carry the date as ?born=2021-04.

Dog years and cat years

Pick dog or cat, enter the age in years and months, and the page gives the human-age equivalent from the American Veterinary Medical Association chart, rounded to a whole year. I know the birth date takes the birth month and year instead and counts whole calendar months up to this month by your device's clock: a dog born in April 2021 is 5 years 6 months old in October 2026, which the chart puts at 39. The day is not asked, so the age can run up to a month ahead. The chart itself is printed under the calculator, so you can read off any age from 1 to 16. A 5-year-old dog or cat is 36; a 10-year-old cat is 56 and a 10-year-old medium-sized dog is 60. The AVMA calls these approximate calculations and suggests asking your veterinarian.

How the AVMA chart is read

Both columns start at 15 human years for year 1 and 24 for year 2. After that the cat column adds 4 a year, to 80 at 16. The dog column, for a medium-sized dog of 21 to 50 lb, adds 4 to 6 a year, to 87 at 16.

Between two whole years the page draws a straight line: a dog of 2 years 6 months is halfway from 24 to 28, so 26. Under a year it draws a straight line from 0 to 15, so 6 months gives 8 after rounding. These in-between figures are the page's arithmetic, not AVMA figures.

  • The chart has no column for small or giant dogs; the AVMA notes that weight and breed influence aging.

  • The chart stops at 16 years, so the page gives no figure above that.

  • Years and months accept decimals; months must be under 12.

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