How old is a 2-year-old dog in human years?

24 by the AKC rule (15 for the first year plus 9 for the second) and about 42 by the epigenetic clock, which front-loads ageing because the first year of a dog's life covers puberty and full growth.

Is a 7-year-old dog a senior?

Roughly 49-62 in human terms. The AVMA calls cats and small dogs senior at about 7, and large or giant breeds as early as 5 or 6, so a 7-year-old Labrador is a senior while a 7-year-old Chihuahua is middle-aged.

How old is a 12-year-old dog?

74 by the AKC rule, 71 by the epigenetic clock. The two methods converge in old age: the clock rises slowly after year ten because DNA methylation changes slow down.

Does the epigenetic clock work for puppies?

No: 16 ln(age) + 31 is defined for dogs one year and older (at 6 months it would give nothing), and it was measured in 104 Labradors, so use it as a second opinion for adult dogs, not for puppies or as a breed-specific figure.

How old is my cat in human years?

International Cat Care: 15 at one year, 24 at two, then 4 human years per cat year: 36 at five, 56 at ten, 76 at fifteen, 96 at twenty.

How old is my dog in human years? Table from 1 to 16

A 7-year-old dog is about 49 in human years by the American Kennel Club rule and about 62 by the UC San Diego epigenetic clock; neither is 49. The table below runs from 1 to 16 dog years with both methods next to the old "times seven", then the cat table from International Cat Care. Small dogs age slower after year two and giant breeds faster, which no single formula captures.

Open the dog age calculator

Dog years to human years, 1 to 16

AKC rule: 15 human years for the first dog year, 9 for the second, 5 for each year after (medium-sized dog). Epigenetic clock: human age = 16 x ln(dog age) + 31, from DNA methylation in Labradors (UC San Diego, 2019-2020). The last column is the old rule of thumb, for comparison only.

Dog age in human years
Dog years	AKC rule	Epigenetic clock	Times seven (old rule)
1	15	31	7
2	24	42	14
3	29	49	21
4	34	53	28
5	39	57	35
6	44	60	42
7	49	62	49
8	54	64	56
9	59	66	63
10	64	68	70
11	69	69	77
12	74	71	84
13	79	72	91
14	84	73	98
15	89	74	105
16	94	75	112

Cat years to human years

Cat age in human years (International Cat Care)
Cat years	Human years
1	15
2	24
3	28
5	36
7	44
10	56
12	64
15	76
18	88
20	96

Size changes the answer

Large dogs age faster: giant breeds are senior at 5 or 6, small breeds at 7 or later (AVMA). The AKC rule fits a medium dog; for a Great Dane the years after two count for more, for a Yorkshire terrier for less. The dog age chart by size has a column for each of the four sizes, years 1 to 16. Type any age in years and months into the dog age calculator to see both methods side by side.

Frequently asked questions

How old is a 2-year-old dog in human years?: 24 by the AKC rule (15 for the first year plus 9 for the second) and about 42 by the epigenetic clock, which front-loads ageing because the first year of a dog's life covers puberty and full growth.
Is a 7-year-old dog a senior?: Roughly 49-62 in human terms. The AVMA calls cats and small dogs senior at about 7, and large or giant breeds as early as 5 or 6, so a 7-year-old Labrador is a senior while a 7-year-old Chihuahua is middle-aged.
How old is a 12-year-old dog?: 74 by the AKC rule, 71 by the epigenetic clock. The two methods converge in old age: the clock rises slowly after year ten because DNA methylation changes slow down.
Does the epigenetic clock work for puppies?: No: 16 ln(age) + 31 is defined for dogs one year and older (at 6 months it would give nothing), and it was measured in 104 Labradors, so use it as a second opinion for adult dogs, not for puppies or as a breed-specific figure.
How old is my cat in human years?: International Cat Care: 15 at one year, 24 at two, then 4 human years per cat year: 36 at five, 56 at ten, 76 at fifteen, 96 at twenty.

How old is my cat in human years? Table from 1 to 20
Year-by-year cat age in human years (15 at one, 24 at two, then four a year), the life stages, when a cat is senior, and how the dog rules differ.
Dog age chart by size: small, medium, large and giant dogs
The AKC chart of dog years to human years for small, medium, large and giant dogs, years 1 to 16, next to the 15/9/5 rule, weight cut-offs and when each size is senior.
How many cups of dog food per day?
Cups of kibble a day by dog weight from the calories on your bag: tables for 300 to 450 kcal per cup, inactive and active adults, and meals.
How much should I feed my dog? Grams and cups by weight
Daily calories and grams of dry food for dogs from 2 to 50 kg, inactive and active, on foods from 3,400 to 4,000 kcal/kg, with the WSAVA chart range.

Sources

NRC 2006, Nutrient Requirements of Dogs and Cats — adult, puppy and kitten energy equations
WSAVA, Calorie Needs for Healthy Adult Dogs (July 2020) — chart range for dogs
WSAVA, Calorie Needs for Healthy Adult Cats (July 2020) — chart range for cats
AAHA 2021 Nutrition and Weight Management Guidelines — weight loss at the resting requirement of the target weight

Published 2026-09-15, last updated 2026-09-17. Figures are starting points from the published equations: individual animals vary by up to 30%, so adjust by body condition and ask your vet for puppies under 8 weeks, pregnancy, lactation or any illness.

Dog years	AKC rule	Epigenetic clock	Times seven (old rule)
1	15	31	7
2	24	42	14
3	29	49	21
4	34	53	28
5	39	57	35
6	44	60	42
7	49	62	49
8	54	64	56
9	59	66	63
10	64	68	70
11	69	69	77
12	74	71	84
13	79	72	91
14	84	73	98
15	89	74	105
16	94	75	112

Dog years	AKC rule	Epigenetic clock	Times seven (old rule)
1	15	31	7
2	24	42	14
3	29	49	21
4	34	53	28
5	39	57	35
6	44	60	42
7	49	62	49
8	54	64	56
9	59	66	63
10	64	68	70
11	69	69	77
12	74	71	84
13	79	72	91
14	84	73	98
15	89	74	105
16	94	75	112